LIBRARY OF CONGRESS. 



Chap. Copyright No. 



Shelf../ 



UNITED STATES OF AMERICA. 



i 



r 



INTRODUCTION TO THE 
STUDY OF MEDICINE 



BY 

G. H. ROGER 

PROFESSOR EXTRAORDINARY IN THE ' FACULTY OF MEDICINE OF PARIS 

MEMBER OF THE BIOLOGICAL SOCIETY 

PHYSICIAN TO THE HOSPITAL OF PORTE-D'AUBERVILLIERS 

\ 

AUTHORIZED TRANSLATION BY 

M. S. GABRIEL, M. D. 
WITH ADDITIONS BY THE AUTHOR 



NEW YORK 
D. APPLETON AND COMPANY 

1901 



Librwry oi Cono 

Two Copies I 
JAN 19 1901 

(1 Copyright entry 



SECOND COPY 



o 




Copyright, 1901, 
By D. APPLETON AND COMPANY. 



TRANSLATOR'S PREFACE 



The rapid and marvellous developments recently made along 
the lines of medical sciences have rendered the task of both teacher 
and student increasingly difficult. It is not strange, therefore, that 
the medical faculty of the University of Paris has instituted a 
course of lectures especially intended for those entering upon the 
laborious study of the medical sciences. 

To Professor Roger, whose experience, both with experimental 
pathology and clinical medicine, is of the widest range, this course was 
intrusted, and, as can be seen, he has accomplished the task most 
admirably. With this book he reveals to the student an immense 
horizon, presenting to him a comprehensive view of ensemble and 
constantly arresting his attention with facts and principles of para- 
mount importance. Not alone the student, but also the practitioner 
who would ever keep fully abreast with the times, will find in this 
work a masterful resume of recent medical advancement. To read 
it is to undertake a fascinating journey into those regions of medi- 
cine where the most important developments have recently been 
realized. 

The chapter upon the examination of the sick will prove highly 
gratifying even to practitioners of considerable clinical experience. 

The glossary of the French text has been omitted in this trans- 
lation and an elaborate index substituted therefor. 

In view of the alterations and additions which Dr. Roger kindly 
furnished me, this translation may be considered a second and re- 
vised edition of the work. 

M. S. Gabkiel, M. D. 

New York, October 27, 1900. 



in 



AUTHOR'S PREFACE 



This book is a reproduction of the course of lectures delivered by 
me in 1897-98 at the University of Paris. The object of my teach- 
ing was to lessen as much as possible the difficulties met with in 
the study of the medical sciences. 

We all know from experience how much time is wasted by not 
knowing with what subject to begin, what books to read, and also 
by being compelled frequently to refer to a dictionary for an ex- 
planation of technical terms encountered. With the view of reliev- 
ing beginners of much useless embarrassment, the Faculty of Medi- 
cine intrusted me with the course of lectures which I now publish. 

The plan adopted is a very simple one. I have endeavoured 
to show what is the object of medicine, and by what means it may 
be studied. After having explained why and how an individual 
becomes sick, I have considered the morbific causes which constantly 
tend to modify the unstable state of health. These causes give 
rise to manifestations through the lesions and reactions they deter- 
mine, some of which can be detected only after death, while others 
are appreciable during life. We are thus led to study the mode 
of reaction of the organism — namely, pathological physiology — to 
describe the organic changes constituting pathological anatomy, and 
to look for functional disturbances, the description of which forms 
an important chapter, semeiology. 

Although I have devoted over two hundred pages to the con- 
sideration of the examination of the sick, I have done no more than 
present some general considerations with reference to the rules 
which should be followed by the physician in his practice. I earnestly 
hope, however, to have succeeded in demonstrating that it is pos- 



vi INTRODUCTION TO THE STUDY OF MEDICINE 

sible to , make a diagnosis and prognosis by simple means within 
the reach of all. It seemed to me important to oppose the tend- 
ency of some modern authorities who think the solution of prob- 
lems raised by the examination of patients can be found in labora- 
tory researches. No one is more firmly convinced than myself of 
the usefulness of experimental pathology. Nevertheless, at the bed- 
side the physician can do no better than to depend upon clinical 
procedures. Only in quite rare instances will he be obliged to resort 
to more delicate methods of investigation. I can not admit abdica- 
tion of clinical methods of investigation before the rising tide of 
bacteriology. 

It is likewise in clinical experience that we find the indications 
of procedures enabling us to favourably modify the evolution of 
disease. This part of medicine constitutes therapeutics, to the study 
of which the last chapter of this book is devoted. 

From these explanations it can be seen that I have, step by 
step, followed the course of morbid processes, thus endeavouring 
to construct a frame in which the descriptions of general or spe- 
cial pathology can be placed. 

Addressing students especially, I have, as a rule, avoided the- 
oretical discussions and reported only those results which appeared 
to me to be final. I have also excluded doubtful hypotheses and 
contestable conceptions. 

Demonstrated theories and well-established facts become inde- 
pendent of those investigators who made them known. In propor- 
tion as science is brought to perfection it becomes impersonal; hence, 
I have to a great extent been able to ignore citations of proper 
names, confining myself to final achievements. I have explicitly 
mentioned only those old authorities who have made some impor- 
tant discovery, advanced some particular theory, or recorded some 
observation of consequence. Although I have on several occasions 
mentioned researches pursued by myself, I have, following the above 
rule, reported them just as I have those of other authorities, with- 
out indicating their origin. This appears to me to be the only way 
to avoid the unworthy questions too often raised by discussions of 
priority. 



CONTENTS 



CHAPTER PAGE 

Translator's preface iii 

Author's preface N v 

I. — Introductory remarks 1 

II. — Mechanical agents 13 

III. — Physical agents 34 

IV. — Chemical agents 61 

V. — Animate agents . . . . .81 

VI. — Animate agents {continued) 93 

VII. — Animate agents {concluded) 119 

VIII. — General etiology of infections 133 

IX. — General pathogenesis of the infectious diseases .... 158 

X. — Nervous reactions .173 

XI. — Disturbances of nutrition 184 

XII. — Disturbances of nutrition {continued) — Auto-intoxications . . 196 

XIII. — Pathology of the fcetus — Heredity 210 

XIV. — Inflammation 243 

XV. — Septicaemia and pyaemia 285 

XVI. — Evolution of inflammations — Sclerosis . . . . . 295 

XVII.— Tumours 305 

XVIII. — Cellular degenerations 317 

XIX. — Functional synergies and morbid sympathies 328 

XX. — Evolution of diseases . . 355 

XXI. — Examination of the sick 403 

XXII. — Clinical application of scientific procedures .... 492 

XXIII. — Diagnosis and prognosis 513 

XXIV.— Therapeutics .522 

Tables for reducing the metric system into the English . . 537 

Index /- 539 

vii 



INTRODUCTION TO THE STUDY OF MEDICINE 



CHAPTER I 

INTRODUCTORY REMARKS 

Definition of the words medicine, health, disease — Disease and affection — The 
causes of diseases : division, according to the nature of the pathogenic agent, 
into mechanical, chemical, and animate causes; division, according to the 
action on the organism, into efficient, accessory, predisposing causes — Object 
of the various branches of pathology — The bases of therapeutics. 

Medicine is sometimes considered as a science, sometimes as an art. 
Both conceptions are correct ; all depends upon the view point at which 
we place ourselves. Medicine is a science by its means of study; it is 
an art by its applications. We are thus led to the following two defi- 
nitions : 

The object of medical science is the study of disease. The aim of 
medical art is to restore and maintain health. 

That part of medical science which studies disease is called pathol- 
ogy (v-ados, suffering, ailment). The teaching of the medical art, as it 
is done at the sick bed, constitutes clinics (k\lvlk6s, from KXivrj, bed). 

Pathology comprises the following chapters : Etiology (atrta, cause), 
which investigates the morbific causes; pathogeny, which explains by 
what mechanism these causes act on the living organism to disturb 
its state of health or abolish its existence; pathological physiology, 
which shows how the organism reacts (morbid reactions) under the 
influence of pathogenic causes ; pathological anatomy, which unveils the 
structural modifications resulting from the morbid actions and reac- 
tions; symptomatology, which gives an account of the disturbances 
and lesions appreciable during life; nosology, which describes and classi- 
fies diseases. To these different branches, which constitute the medical 
science, should be added two others concerning rather the medical art — 
namely, the technical side (rexv^, art) of medicine; I refer to diagnosis 
and prognosis. Diagnosis (discrimination, from Sia, through, and 
yiyvwcnceii/, to know) determines the place which the disease occupies in 
nosology; prognosis (from irpo, before, and yiyvwovcetv, to know) tries to 
foretell the evolution of the disease. 

1 



2 INTRODUCTION TO THE STUDY OF MEDICINE 

The indispensable complement of pathology is therapeutics, with 
surgery, prophylaxis, and dietetics. Therapeutics (OepaTrevav, to take 
care) is that part of the medical art which, profiting by the scientific 
data furnished by materia medica and pharmacology, endeavours to 
relieve the sick and to modify favourably the evolution of the disease. 
Surgery is that branch of therapeutics which proposes to cure by means 
of manual procedure (x^povpyta, from x«p, hand, and Ipyov, work). 
Prophylaxis {-n-po^vXaa-a-eiv, to watch) whose principal part is repre- 
sented by hygiene (vyUia, health), dictates the precepts to be followed 
for avoiding disease. Dietetics (SiWa, regime) indicates the diet con- 
ducive to the restoration or preservation of health. 

Pathology embraces, then, nearly all of medicine. There is a mani- 
fest disproportion between its vastness and the limitations of the human 
mind; hence the necessity of dividing its study into several distinct 
branches. The following divisions are generally admitted: Special or 
descriptive pathology, which makes an analytical study of diseases and 
comprises internal or medical pathology and external or surgical 
pathology; comparative pathology, which takes into consideration dis- 
eases in man, in animals, and even in vegetables ; experimental pathol- 
ogy, which proposes to modify the evolution of spontaneous diseases 
and to reproduce, with a view of explaining and combating them better, 
the disturbances, lesions, and diseases with which we have been ac- 
quainted through observation; finally, general pathology, which defines 
the terms and fixes their meaning, determines the laws of morbid phe- 
nomena, investigates the causes, processes, and symptoms, and classifies 
them. It outlines the rules of nosology, and prepares the frames in 
which special pathology will place its descriptions. Although general 
pathology is often considered as the synthesis, that is, the loftiest 
part of medical science, and often rises to sublime conceptions well 
calculated to seduce and captivate the mind, it may well be contented 
with more modest views; it may be elementary and furnish the begin- 
ners with rules to guide in their studies of diseases. When we know 
which are the morbific causes most frequently intervening, when we are 
sure of their mode of action and have understood the mechanism of 
morbid reactions, derangements, symptoms, and lesions, we are pre- 
pared to understand and appreciate particular cases. 

We have repeatedly made use of the words health and disease. These 
two words are currently employed ; but, while there is a universal agree- 
ment as to their meaning, there arises considerable difficulty when an 
inquiry is made into the precise nature of phenomena designated by 
these terms. The same is true of all abstract ideas : only those subjects 
are well defined whose limits can be comprehended by the mind. 
Health and disease (or hygid state and morbid state) are connected 



INTRODUCTORY REMARKS 3 

by a multitude of disturbances more or less well characterized; it is 
therefore very difficult, not to say impossible, to draw a sharp line be- 
tween these two states, which, absolutely different in their highest 
expressions, approach and unite with each other in their attenuated 
manifestations. The difficulty is rendered greater by the fact that 
perfect health does not exist; living organisms are always in a state 
of unstable equilibrium, which finds its explanation and cause in the 
very conditions of life. 

It is known, in fact, that living matter is the seat of a series of acts 
which do not depend, as was once believed, upon a vital force animating 
matter, but should be considered as reactions produced by the variations 
of external agents. 

Let us suppose for a moment that no modification whatever is pro- 
duced in the cosmic forces, no change at all in the relations of a being 
with the objects that environ it : equilibrium will soon be established 
between this being and the surrounding world. ■ Of course, life is not 
annihilated under these conditions ; but it remains latent, as was once 
said, or, to speak more correctly, remains in a static state. But the 
moment an external variation occurs, the equilibrium is broken; the 
living organism, to adapt itself to the new conditions, presents a series 
of reactions making life again apparent — that is, causing it to pass 
into the dynamic state. Now, in reality, the cosmic forces constantly 
vary, the objects are displaced and modified; the world we live in 
changes, and, life being but an adaptation to medium, living matter is 
incessantly agitated by reactionary oscillations calculated to counter- 
balance the influence of the external agencies. Thus is explained the 
unstable state just referred to. 

If neighbouring variations are slight and slow, adjustment is read- 
ily made and health preserved. Should they be intense and sudden, 
compensation becomes more difficult, often resulting in indisposition, 
sickness, or death. Let us suppose, for example, a man placed in a room 
with a fixed temperature of 20° C; the organism of this man 
is regulated so that the production and dissipation of heat maintain 
his organic temperature at 37° C. As the medium is supposed 
to be constant, heat production will be managed also in an invariable 
way. Suppose, now, that the temperature of the room rises or falls 
one degree; the equilibrium is disturbed and thermogenesis modified. 
In order that his temperature may always remain at 37° C, he must 
either produce more heat or expend less. When the variation is light 
and progressive, adjustment is made easily and unconsciously; the 
organic modifications are not perceived and do not cause any trouble. 
But if the temperature of the room should suddenly rise from 20° to 
80° C, or fall to — 40° C, this change of 60° in plus or minus would 



4 INTRODUCTION TO THE STUDY OF MEDICINE 

completely upset the thermogenic equilibrium of the organism and 
provoke a series of disorders resulting in disease or a fatal ter- 
mination. 

What we say about heat can be repeated with regard to other phys- 
ical agents. Barometric variations, imperceptible when slight, give rise 
to indisposition when intense. If it is a question of considerable change 
of pressure — for instance, when making a balloon ascent, or when one 
is submitted to the action of compressed air, and especially when one 
is caught in a gas explosion — the accidents may prove very serious, or 
even fatal. 

Physical variations are not the only ones capable of impressing the 
organism ; all modifications occurring in our relations with surrounding 
objects and beings may produce the same effect. It is therefore possible 
to transport into medicine the classical data of the physical and natural 
sciences and divide the pathogenic agents simply into four groups : Me- 
chanical agents; physical agents; chemical agents, including the caustics 
and the toxics; animate agents, subdivided into parasitic and infectious 
(the latter including most of the pathogenic bacteria). This enumera- 
tion shows that diseases are not provoked by new, special, mysterious 
causes, but by the ordinary cosmic agents — by the objects and beings 
that surround us. When impressed by these various agents, the organ- 
ism, as above noted, does not remain indifferent; it responds by reac- 
tions, whose purpose, if not the effect, is to bring the economy to a state 
compatible with life. Therefore two orders of phenomena are to be 
noticed in every disease : those due directly to the cause and those refer- 
able to the reaction of the organism. The latter are far more important 
than the former. In a good definition, however, we must, following Dr. 
Bouchard, take into account both series of morbid manifestations. We 
are thus led to the following definition : 

" Disease is the ensemble of the phenomena which are produced in 
an organism undergoing the action of a morbific cause and reacting 
against it." 

We have thus far supposed this morbific cause to be exogenous — i. e., 
outside of the organism. But authors often attribute disease to inter- 
nal or endogenous causes — that is, causes taking origin within the 
organism. We have excluded this etiological group for the reason that 
it is no longer acceptable ; all diseases, indeed, proceed from an external 
cause. The opposite view is due to a persistent confusion of disease 
with affection. 

Take, for instance, a man suffering from typhoid fever. The disease 
being over, the organism is restored to health. But the restoration is 
only apparently perfect; modifications persist which, too slight to be 
perceived, follow nevertheless their progressive evolution. Ten, fifteen. 



INTRODUCTORY REMARKS 5 

twenty years later, new manifestations break out — for example, some 
disturbances due to heart lesion. By that time the disease is almost 
forgotten, and, as no intermediate bond connects the actual manifesta- 
tions with the disease left far behind, considerable difficulty is experi- 
enced in tracing the succession — some sort of repugnance to connect 
this cardiopathy with the long expired typhoid fever. In another case 
the subject will have been through a number of different diseases, and 
the physician will be at a loss as to which of them to attribute the new 
visceral disorder. 

From a philosophical point of view it is essential to reascend to the 
first disease. From a practical standpoint this inquiry is often use- 
less. Whatever the etiological conditions may have been, the effect is 
the same. Organic affections are simply cicatrices; disengaged from 
the initial cause, they become autonomous and develop on their own 
account. 

Let us take up the example above referred to. Suppose a man suf- 
fering with a cardiac affection. Whatever the starting point of the car- 
diopathy may have been, whether rheumatism, typhoid fever, or any 
other disease, the effects are identical. The new morbid manifestations 
derive no particular character from their origin. The etiological notion 
is of no practical importance, but is indispensable to the nosologist 
who will even refuse to consider the affections of the organs as 
diseases. 

What is true of the heart is true of all the viscera. Their affections 
take origin from some antecedent cause. For a long time this very 
simple truth has not been understood because the initial disease is 
not always easily found out ; the visceral derangement may be the first 
outward manifestation, leading to the belief that it is making its appear- 
ance spontaneously. 

To those who should wonder how a visceral lesion is capable of devel- 
oping silently for twenty or thirty years without giving rise to any 
symptom, we can answer by the well-known example of gonorrhoea. 
A man has a urethral discharge at the age of twenty; he recovers in a 
few months, and seems to be completely cured. Toward the age of 
forty or fifty micturition grows difficult, and a urethral stricture is 
discovered, which nobody hesitates to connect with the former attack 
of gonorrhoea. It is a remnant of the infectious process, a cicatrix that 
has shrunken little by little. Why, then, should we regard as doubtful 
in the ease of the viscera and organs that which is so readily admitted 
to be true as regards the urethra ? The process is alike in both cases ; 
it is one of cicatricial evolution, slow and progressive. 

We can therefore, in the presence of these tardy manifestations, 
sequelae of diseases, isolate the exciting cause ; but on condition of being 



6 INTRODUCTION TO THE STUDY OF MEDICINE 

mindful of the fact that the actual disorders are due to an anterior 
cause which voluntarily we disregard. 

When the actual morbid process is considered without taking into 
account its initial cause, the name disease can not be applied to it. It 
is preferable to employ the term affection. We shall define, there- 
fore: "Disease is the morbid process considered in its entire evo- 
lution, from its initial cause to its final consequences; affection is 
a morbid process considered in its actual manifestations, apart from 
its cause." 

It is improper to speak of diseases of organs ; affection is the proper 
term. Some authors use, in this sense, the term pathy as a suffix 
following the name of the organ. The word thus created indicates an 
affection of this organ, without prejudging the disease. This procedure, 
strongly advocated by Dr. Landouzy, is perfectly rational. The words 
cardiopathy, pneumopathy, etc., have the advantage of being both well 
constructed and very suggestive ; " cardiopathy " is simpler than " car- 
diac affection " and more exact than " heart disease." This nomen- 
clature would put an end to the confusion that has been established and 
maintained between disease and affection. 

Another condition further complicating the problem is the fact that 
the modifications produced by diseases and affections may^imiuence the 
descendants. Thus is created morbid heredity, which may be transmitted 
through a great number of generations, and may explain the develop-^ 
ment of pathological families. Variously tainted children are brought 
into the world, presenting a defective nutrition and predisposition to 
certain diseases. In this event the disturbances of health are autoge- 
nous so far as the sufferers themselves are considered, but in reality 
they are exogenous in that they are the result of external influences 
exerted upon their parents. In pathology, as in biology, the successive 
series of livings beings must be considered as a single being eternally 
existent. 

We shall consider at length, in a later chapter, the role of heredity, 
which explains a group of causes which, at first sight, seem to form an 
exception and to depend upon an internal origin. I refer to psychical 
causes. Psychical phenomena, the highest manifestations of life, 
appear to be independent of the external medium. In reality, though 
more complex, they do not differ essentially from bodily phenomena; 
they are equally dependent upon external agents which have acted upon 
the person himself or his ancestors. 

These considerations amply authorize us to reject absolutely the 
division of morbific causes into internal and external. The initial 
causes are always to be looked for outside the organism. In view of 
their nature they may, as we have said, be classified into four groups: 



INTRODUCTORY REMARKS 7 

Mechanical, physical, chemical, and animate causes. In view of their 
action upon the organism, it is possible to divide them into effitient and 
predisposing causes. 

The efficient causes are always necessary; at times they are suffi- 
cient by themselves. Let us take, for example, the anthrax bacillus, 
which is one of the microbes best studied by experimenters. Let us 
introduce it beneath the skin of a guinea pig. The animal contracts 
the disease and dies within three or four days. In this case the efficient 
cause has proved sufficient. Let us make the same inoculation into a 
more resistant animal, the white rat. No disorder will be produced. 
But let us submit this white rat to some fatiguing exertion, or inject 
into it some toxic substance. The intervention of such an accessory 
cause will favour the action of the efficient cause: the anthrax will 
develop. The more we study pathology and get an insight into the 
history of infections, the better we understand the importance of 
auxiliary causes. There are certain microbes which develop as soon 
as they are deposited on a wound or even a healthy mucous mem- 
brane, but they are exceptions. In most instances various causes 
must come to their assistance. This is especially true of the microbes 
inhabiting our normal bodies. Our integuments and mucous mem- 
branes swarm with innumerable pathogenic agents, which vegetate as 
simple innocent parasites until the day when an auxiliary or, as some 
still say, a determining cause permits them to overcome our resistance 
and exercise their noxious influence ; then appear a series of acts ending 
in indisposition and disease. Pneumonia, for example, is an infection 
induced by a microbe frequently present in the mouth of healthy per- 
sons ; so long, however, as the organism is in a normal state the microbe 
can not develop. But let some common cause — fatigue, cold, or inhala- 
tion of irritating vapours — reduce the resisting power; the microbe, 
until then harmless, becomes pathogenic. This well-known example 
proves that the co-operation of the two orders of causes is indispensable. 
Let us not fall into the error of the first bacteriologists, who thought the 
micro be was sufficient to explain all ; an error less excusable than that 
of the ancient authorities, who, having no idea of the role of animate 
agents, explained morbid phenomena by the intervention of auxiliary 
causes alone ; and hence they believed also in morbid spontaneity. They 
believed in it also because they did not understand the nature and 
mechanism of predisposing causes. They assigned to predisposition an 
internal origin instead of seeing in it the resultant of impressions 
made upon the subject or his progenitors by external causes having 
acted antecedently. Predisposing causes are antecedent causes with 
respect to present disorders; efficient and auxiliary causes are present 

causes. 

2 



8 INTRODUCTION TO THE STUDY OF MEDICINE 

Each pathogenic agent may play alternately the part of efficient 
cause and of auxiliary cause ; heat and cold, for instance, in mortifying 
a tissue, act as efficient causes, but they fall into the order of auxiliary 
causes when they favour the development of a microbe. Likewise a 
microbe or a poison may produce a disease or aid another pathogenic 
agent. We should never lose sight of the possibility of these etiological 
associations, these morbid synergies which play a part extremely impor- 
tant in pathology. 

According to the mode and extent of their action, the pathogenic 
causes are often divided into local causes and general causes. The for- 
mer act on a limited point of the organism, the others act on the entire 
economy, or rather on numerous points thereof. The same pathogenic 
agent may enter into either of these groups. For example, streptococ- 
cus, a kind of microbe, when inoculated subcutaneously, produces a 
local lesion — erysipelas ; when injected into the veins, it gives rise to a 
general infection — i. e., septicaemia. 

Every local lesion presents to study two orders of phenomena: 
those occurring at the point of application of the cause and those pro- 
duced in distant parts. 

At the point where the agent acts, the cellular elements are irri- 
tated, altered, or destroyed. These first disturbances, provoked directly 
by the pathogenic agents, give rise secondarily to responsive phenom- 
ena in the elements that remain alive. These manifestations con- 
stitute what Dr. Bouchard calls primitive autonomous elementary 
dystrophies. 

But the organism is so constituted that a lesion can by no means 
remain local; it soon arouses a series of secondary manifestations, of 
which some are due to nervous reactions, others are caused by the 
absorption and penetration of anomalous substances produced at 
the primary focus. These secondary morbid manifestations represent 
pathogenic processes of a second order. They result in the formation 
of new lesions and the production of new disturbances, which become 
themselves the starting point of manifestations of a third order, and 
so on. The pathological process is thus liable to become extremely com- 
plicated. These successive manifestations are of course of an internal 
order; only the starting point (the primum movens) of the morbid 
series has been an external cause. 

The study of morbid reactions, of which we have outlined the mech- 
anism, constitutes physiological pathology. It is not to be supposed, 
however, that these reactions are essentially different from those ob- 
served in a physiological state. Biological laws are the same in both 
morbid and normal phenomena. It would be an error to believe that 
the living being is able to dispose of different manifestations, some of 



INTRODUCTORY REMARKS 9 

them intended for normal conditions, others for pathological condi- 
tions. The mode of reaction is ever the same ; the results vary only in 
their intensity, but they are directed toward the same end — i. e., they 
always tend to counterbalance the action of external forces. In other 
words, health is organic reaction in fixed and pre-established condi- 
tions ; disease is represented bv reactions of the same nature, but pro- 
duced in variable and new conditions. While the causes vary, the reac- 
tions may remain the same in their essence, notwithstanding the dis- 
similarity of their manifestations. Pathological physiology must not, 
therefore, be opposed to, but simply considered as the consequence of, 
normal physiology. 

The morbid actions and reactions express themselves by functional 
modifications and structural lesions, which may be recognised during 
life or discovered only after death. The structural lesions, the study of 
which constitutes pathological anatomy, must be considered as the 
result of functional disturbances; as we are taught in general biology 
that it is the function that creates the organ, so in pathology it is 
proved that the disturbance of the function is responsible for the 
organic lesion. 

Disturbances and lesions may, as above stated, be disclosed during 
life ; they then constitute the symptoms and signs of the disease, and, 
according as they are perceived by the patient or recognised only by the 
observer, are divided into subjective phenomena and objective phenom- 
ena. In order to study them, we usually begin by interrogating the 
patient and making a list of his subjective symptoms ; next we proceed 
to observe the objective signs by passing systematically in review all the 
apparatus and all the organs. Then comes the task of resolving the 
final problem: the symptoms presented by the patient being given, to 
recognise the disease. A difficult problem, indeed, because error may be 
owing to a bad determination of symptoms as well as to faulty interpre- 
tation of their relative value. Doubtless there are certain cases in which 
the recognition of a single phenomenon suffices to settle the diagnosis ; 
the symptom is then called pathognomonic. But this is exceptional. 
The relative significance of the different symptoms must be determined, 
or, as is sometimes said, their semiological value established. When 
we are through with the methodical analysis of the patient, we must 
make the synthesis of the disease, connecting each trouble with its 
immediate cause, determining the nature and mechanism of the latter, 
and thus ascending the entire scale of successive manifestations until 
we reach the affection or disease which has been the point of departure 
of the morbid series. 

Let us take an example : A man is complaining of pain in the side. 
This subjective phenomenon leads to an examination of the respiratory 



10 INTRODUCTION TO THE STUDY OF MEDICINE 

organs. On auscultation, rales are heard at the base of the lung, indi- 
cating congestion. But pulmonary congestion is not a disease; the 
cause of the trouble is to be looked for. So, pursuing the examination, 
we find out that this man has a cardiac lesion and that the pulmonary 
manifestations are due to the insufficiency of the heart. If we had 
seen no more than the congestion of the lung we might, by treating 
this organ, have done some good to the patient, but we would not have 
cured him. Having recognised that all depends upon the heart, we may 
act upon the cause of the disturbances and obtain far better results. 
By making the diagnosis of cardiopathy, the clinician has thus far 
done enough for practice, but the nosologist has not completed his 
task. He knows there is no organic disease ; he must, therefore, discover 
the cause of the cardiac lesion. Questioning the patient brings to light 
the fact that he has once suffered from an infectious disease, typhoid 
fever or acute articular rheumatism, which has given rise to endo- 
carditis ; this explains all. We have discovered the primary disease, of 
which the present affection is but the sequel. So far, however, as 
treatment is concerned, this disease is of no importance; the patient 
is not suffering from typhoid fever or rheumatism, but from a cardi- 
opatlry, and the medication will be the same, no matter what may have 
been the cause of the affection. 

It is not to be supposed, however, that it is useless to inquire into 
the causes. Here is a man who has lost the faculty of speech; he is 
attacked with aphasia. Now, aphasia is dependent upon a lesion of the 
third frontal circonvolution of the left side. Taking our stand upon 
antecedent or concomitant troubles, we diagnosticate a tumour pressing 
upon the cortical centre of speech. If we stop there in our diagnosis, 
we shall have recognised a cerebral affection, and might tell the patient 
there is no efficacious treatment for it. But, pushing farther our 
analysis, we discover on the skin old cicatrices revealing the existence 
of an ancient syphilis. At this point our diagnosis is complete, and 
leads us to institute the specific treatment which will cure the patient. 
In this case inquiry into the causative disease has led to the etiological 
therapeutics which alone could be successful. The determination of an 
exact and complete diagnosis is attended by that satisfaction which is 
always experienced when a difficult problem is solved; but, what is of 
greater consequence, it furnishes the precise indications of treatment. 
Unfortunately, in practice, the physician is not appreciated according 
to his skill in determining the nature of a sickness. What the patient 
and his friends require of him is prognosis ; they are, of course, unable 
to verify his diagnosis, but they witness the course and termination of 
the sickness, and according as his predictions are realized or not they 
conclude that the doctor was right or mistaken. 



INTRODUCTORY REMARKS 11 

In a great number of instances prognosis and diagnosis are con- 
nected. A child, for example, presents certain symptoms which, lead ns 
to diagnosticate tubercular meningitis ; the prognosis is then well-nigh 
fatal. On a more careful examination, some rather odd phenom- 
ena might be discovered, and, auscultating more attentively, there might 
be heard a tubal murmur in the thorax. It was not, therefore, a ques- 
tion of meningitis, but simply meningeal accidents dependent upon 
pneumonia. The termination will be altogether different — the patient 
will recover. In this case the error of prognosis is connected with the 
error in diagnosis. 

Prognosis is not always deducible from diagnosis. Besides diseases 
with a well-nigh fixed prognosis, there are others in which prognosis 
totally varies with the forms, the epidemics, the concomitant phenom- 
ena, and the previous state of the subject. On all these questions there 
can be given some general notions that may materially help, but for 
the matter of prognosis, as well as of diagnosis, books and lectures are 
inadequate. The medical art may be learned only by practice. It is 
only by seeing many patients and comparing different cases that one 
acquires the habit of weighing the value of signs which lead to correct 
diagnosis and prognosis. 

In establishing the prognosis, the expected influence of the treat- 
ment should also be taken into account. The therapeutic indica- 
tions are derived from the study of symptoms, causation, pathogenic 
process, and pathological physiology. We may, then, according to 
the indications which serve as our basis of treatment, admit a 
symptomatic, an etiological, a pathogenical, and a physiological thera- 
peutics. 

Symptomatic therapeutics aims to relieve painful symptoms, func- 
tional disorders, and to combat immediate accidents; it appeases and 
assuages, but seldom cures. 

Etiological therapeutics fights the very cause of the evil; it furnishes 
antidotes, vermifuges, antiseptics. The method of treatment is etiolog- 
ical when specific remedies, such as mercury for syphilis, quinine for 
intermittent fever, and salicylate of sodium for rheumatism are pre- 
scribed. 

The morbific cause is often beyond our reach, either because we are 
unable to touch it by our present procedures or because its action has 
been transitory; we must therefore act on the mechanism set in action 
by the cause or on the reactions presented by the organism. This 
would be pathogenical or physiological medication. This is what is 
realized when an attempt is made to restore to the normal rate nutrition 
disturbed by various causes, or to modify nervous reactions, or to neu- 
tralize the effects of microbic toxines. 



12 INTRODUCTION TO THE STUDY OF MEDICINE 

The therapeutic ideal is to realize these rational medications. But 
at present, while it is easy to lay down general indications, it is often- 
times impossible to fulfil them ; the physician must content himself with 
symptomatic treatment, at times even with empiricism. He must still 
resort to statistics, whose data are indispensable in reassuring him as to 
the value of treatments ; he thus secures some tentative results, which 
he will abandon as soon as the advance of science enables him to sub- 
stitute rational for empirical medication. 

We conclude, therefore, that the interest of the study of general 
pathology is not merely a speculative one. It alone can supply guiding 
ideas which will serve as the basis of the medical art. 



CHAPTER II 
MECHANICAL AGENTS 

Medical definition of mechanical agents— Mechanical agents acting by pressure: 
punctures, cuts, contused wounds — Commotion — Compression — Mechanical 
agents acting by distention — General reactions — The influence of passive 
movements — Seasickness. 

From a medical standpoint, mechanical agents may be denned as 
" all those that tend to modify the state of rest or motion of a por- 
tion or the entirety of a living body — i. e., to modify its position 
in space." 

There may be three examples : 

1. The mechanical agent is a body in motion; it encounters a living 
being opposing a resistance to it. 

2. The mechanical agent represents the resistance, and the hnman 
body the power. Such is the case when a man falls from a certain 
height. 

In these two instances, although the mechanism is different, the 
result is the same. There is a conflict between power and resistance. 

3. The third group, of far less importance, comprises those agents 
tending to impart motion to the whole body, as occurs when we find 
ourselves on a moving object or a boat agitated by the sea. 

Let ,us consider first the results of the conflict ensuing between an 
agent in motion and a living being. It is said in mechanics that such 
an agent is endowed with kinetic energy. This force is equal to half 
the product of its mass into the square of its velocity, as expressed by 

M V 2 

the well-known formula — E = J — — . 

This formula has considerable interest for us. 

Let us suppose a missile having a mass equal to a unit whose speed 
at the moment it reaches the living body is equal to 1 ; the energy will 
evidently be represented by -|. 

If the mass becomes 20, 100, 1,000 times greater, the velocity re- 
maining the same, the energy increases as half of these figures and be- 
comes 10, 50, 500 times greater. 

13 



14 INTRODUCTION TO THE STUDY OF MEDICINE 

If the velocity increases in the proportion of 20, 100, 1,000, the 
energy increases as half of the square of these figures — i. e., as 200, 
5,000, 500,000. Thus, while the mass increases as 1,000, the energy 
increases as 500 ; the velocity increasing as 1,000, the energy increases 
as 500,000. This clearly shows that the effects produced by the wound- 
ing body are directly in relation to the velocity acquired. Here is the 
whole secret of the action of mechanical agents, and notably of fire- 
arms. A bullet of the Lebel rifle is 8 millimetres in diameter and 
weighs 15 grammes; the ravages which it produces depend merely 
upon its velocity, which, at the starting point, is 631 metres per second 
and is expressed by an energy of 344 kilogrammetres. 

In order to understand the action of mechanical agents, we must 
take into account two factors : their power — i. e., their energy — and 
their direction. 

The power of a wounding agent is easily determined. Besides its 
speed, we have to consider its mass or, what is simpler, its weight, its 
density, and its volume. We must, moreover, take into account its 
form, and the projections or inequalities of its surface. We can not 
dwell upon the importance of the various conditions just enumerated ; 
it is not difficult to understand their multiple effects. In the case of 
a war projectile it is quite certain that, assuming the energy to be the 
same, the injury produced will be the less serious the less voluminous, 
the smoother, and more resisting the wounding body is, so as to pass 
through the tissues without bursting. 

The effects vary also according to the direction of the mechanical 
agent — i. e., according to the angle at which it strikes the living being. 
A projectile may enter a member of the body perpendicularly, obliquely, 
or parallel to its axis. The oblique course is evidently longer and 
causes far greater injury. In the case of a parallel course, the projectile 
may simply run beneath the skin without touching any important part. 

In order to introduce harmony into the study of mechanical agents, 
it has been necessary to adopt a certain number of divisions. Two great 
classes may be admitted, according as the pathogenic agent acts by 
pressure or by traction. 

Mechanical Agents acting by Pressure 

The mechanical agents acting by pressure are the most important. 
They are divided into three groups, according to the extent of their 
surface of contact. According as they terminate in a point, a line, or 
a plane, they are designated as puncturing, incising, or contusing 
agents. 

Punctures. — A puncture may be produced by very slender objects, 
as needles, pins, cannulae of hypodermic syringes, by splinters, or the 



MECHANICAL AGENTS 15 

sting of certain animals, insects, arachnida, and scorpions. In other 
cases they are due to instruments with an abrupt enlargement above 
their termination — e. g., swords. The effects differ, of course, accord- 
ing as the puncture is a small or a large one. 

In the first instance no notable accident is generally produced. The 
puncture with a needle, or a pin, or a splinter causes slight pain, loss 
of a drop or two of blood, and then cicatrization is rapidly effected. 
No greater harm results when the objects are a little more voluminous, 
as bodkins or various instruments employed in the industries. The 
only danger is that the pricking agent may be charged with toxic sub- 
stances (poisonous punctures, poisoned arrows) or contaminated with 
microbes, which invade the little wound. Such punctures, designated as 
septic, will be considered in connection with infections. 

It may also happen that the instrument remains in the wound, as 
is particularly the case when it breaks. The foreign body may remain 
for years in the tissues without giving rise to any inconvenience. Some- 
times the agent wanders in the organism and finally protrudes in a 
region often very far removed from the point through which it origi- 
nally entered. 

In a general way, it may be stated that the tissues tolerate for- 
eign bodies that have merely a mechanical action. The exceptions 
to this rule are only apparent. Several experimenters have seen 
nodular lesions, analogous to tubercles, develop around grains of 
lycopodium, Cayenne pepper, and oyster shells. It must be ad- 
mitted that in such instances the foreign body had not acted in a 
merely mechanical manner; an infinitesimal part underwent solution 
and excited irritation in the neighbourhood. Although it may be ob- 
jected that the question is often one of insoluble bodies, it must be 
remembered that numerous researches have established the fact that 
living cells are influenced by quantities of substances so minute that 
no chemical test can detect them. Bodies reputed to be insoluble may 
in reality be dissolved in a quantity sufficient to give rise to reactions on 
the part of the. organism. 

It is well to recall here the brilliant experiments of Eaulin, who 
proved that the aspergillus can not grow in a silver vessel. The liquid 
contained in the vessel dissolves an amount of the metal which no re- 
agent except the living cell can reveal. Naegeli likewise established the 
fact that a gold coin placed in a glass of water diffuses sufficient copper 
to arrest the development of spirogyra. One part of a copper salt per 
1,000,000,000 suffices to cause the plant to perish. These results are 
not only of interest to the naturalist; they lead to the admission that 
foreign bodies, whatever they may be, exert no pathogenic action 
except when they pass into solution. A foreign body which remains 



16 INTRODUCTION TO THE STUDY OF MEDICINE 

absolutely insoluble will be tolerated by the tissues and call forth 
no reaction. 

To return to the mechanical action of pricking bodies. We have to 
consider the effects produced by them on various parts of the organism. 
Let us first direct attention to the blood vessels. Punctures are well 
borne by these structures. Blood is quite frequently drawn from veins 
for diagnostic purposes. A Pravaz syringe cannula, for instance, is 
introduced and a small amount of blood withdrawn. This method, 
which had already been employed by Davaine, is often employed at pres- 
ent, and never causes any accident when the needle is aseptic. Like- 
wise, intravenous injections may be practised on man, as well as on ani- 
mals, by the introduction of a cannula through the. unbroken integu- 
ments. A little ecchymosis, if anything, is produced, which, however, is 
of no importance. 

Puncture of arteries is just as harmless. The muscular coats of 
these vessels insure perfect closure. Intra-arterial injections may be 
made in this manner in animals, at least in dogs. In rabbits, however, 
the musculature is insufficient, and puncture of an artery by means of a 
Pravaz needle gives rise to very grave hemorrhages. 

In man, puncture of aneurismal sacs is frequently practised. Very 
fine needles, called Japanese needles, electrodes, and watch springs are 
introduced. The wound is too small to allow the escape of blood. 

Even the heart has been punctured. The experiments of Sanc- 
torius, of Plater, and especially those of Bretonneau and Velpeau, estab- 
lished the possibility of the introduction of needles into the heart of 
animals without danger. At the present day experimenters in physio- 
logical laboratories frequently make use of long needles terminating 
in a little flag. These are thrust into the cardiac cavities in order to 
observe the movements of this organ. Practised on dogs and rabbits, 
this experiment is unattended by bad effects, and it does not even seem 
to be painful. In view of these experimental results, it has been pro- 
posed to practise abstraction of blood from the heart in man. This 
therapeutic measure, consisting in the introduction into the right ven- 
tricle of a thin needle connected with an aspirating apparatus, can not 
be accepted without reservation. For even if it be true that in most 
cases puncture of the heart is harmless, that pins and sword points 
have been found in this organ which endured them without inconven- 
ience, still such is not always the case. Some persons have suddenly 
succumbed in consequence of a simple, nonpenetrating wound (as in the 
famous case of Latour d'Auvergne). An observation of Dr. Magnan is 
very interesting in this connection : An insane woman succeeded in com- 
mitting suicide by means of a pin, three centimetres long, which she 
drove into her heart at the level of the apex. At the autopsy it was 



MECHANICAL AGENTS 17 

seen that she had made eight punctures in her heart, but none of them 
had traversed the muscle. 

Puncture of a nerve causes intense pain, and, what is of more 
importance, it may be followed in certain instances by a rebellious 
neuralgia. 

Puncture of the nervous centres is not serious except when it touches 
the point described by Flourens under the name noeud vital. Then it 
causes sudden death through arrest of respiration. In several instances 
criminals have killed their victims by puncturing them at this point. 
In this manner, also, a certain number of infanticides have been per- 
petrated. 

Punctures of the viscera do not generally produce any accident. 
For purposes of clinical exploration or therapeutic intervention, the 
spleen, liver, and lungs have often been punctured. In emptying a 
hydrocele the trocar has perchance been driven into the testicle without 
any harm resulting. 

Even when a reservoir full of liquid is punctured, closure is easily 
effected. In cases of retention of urine, the bladder is frequently punc- 
tured, and even the intestine has been submitted to the same operation. 
In the latter case the puncture is closed by a little hernia of the intes- 
tinal mucous membrane; not a single drop of the intestinal contents 
escapes into the peritoneum. This fact has been applied with benefit 
in the treatment of tympanites caused by intestinal obstruction. But 
the procedure is not altogether free from danger, and it has therefore 
been abandoned. Lastly, from a medico-legal standpoint, it is well to 
remember that puncture of the foetal membranes by means of a needle 
introduced through the cervix of a gravid uterus is one of the proced- 
ures most frequently adopted to induce criminal abortion. 

In the case of large punctures, such as those produced by a sword 
thrust, the effects are often without gravity, especially when the wound 
is situated in a limb. 

Wounds of the two great cavities of the body are divided into non- 
penetrating and penetrating, according as the wounding agent stops in 
the wall or traverses it. In the latter case the wounds are designated as 
simple or complicated, according as the viscera are involved or not. 
In some instances swords have passed through the thorax or the abdo- 
men without touching the organs. Such occurred in the case of a young 
man presented by Despres at the clinics of Berard (1843) . He fell from 
a cherry tree, 3 metres high, upon a prop which penetrated the back 
and made its exit above the pubes, fixing itself farther in the thigh. 
Passers-by removed him from the pole and he was taken to a hospital, 
where he rapidly recovered. 

A sword may pass through the thorax, making its way across the 



18 INTRODUCTION TO THE STUDY OF MEDICINE 

pleura without separating its layers or giving rise to a pneumothorax. 
In certain cases the sword may strike the vertebral column and there 
be broken. It may then become encysted at this point without incon- 
venience, even though it has passed through the lung. Yelpeau had 
the opportunity of making an autopsy upon the body of a man who 
had had a foil broken in his thorax fifteen years before. He found in 
the interior of the lung the iron blade, which measured 8.5 centimetres 
in length. 

However, when the organs are injured certain disturbances are 
generally produced, among which two phenomena are most important — 
namely, hemorrhage, sometimes sufficiently profuse to cause death, and, 
in case of injury to intra-abdominal reservoirs, escape of the liquid con- 
tents from within the wounded organ. 

Cuts. — Cuts are solutions of continuity produced by instruments, 
such as knives, saws, sabres, and also by splinters of glass and pottery. 
In this group are to be included the cuts sometimes caused by a sheet 
of paper or a tensely stretched wire. Finally, although the mechanism 
is more complex and the cut may be complicated with contusions, we 
may add to this list the great damage caused by the horns of animals, 
notably of cattle. 

In order to recognise the nature and gravity of the accidents pro- 
duced by cutting agents, we must take into account their weight, the 
force with which they strike, and also their direction. If a knife is 
simply thrust into the tissues the wound produced is much less grave 
than when care is taken to modify its direction after introduction — i. e., 
to raise or lower the handle. Under such circumstances the person 
using the knife is more certain to strike some important organ and to 
injure it to a great extent. 

All tissues are not affected in the same manner by cutting instru- 
ments. In this regard the following rules have been established : 
Tensely stretched parts are incised; soft parts are crushed; hard parts 
break. These formulas, however, are not absolute. In certain instances 
a bone, instead of breaking, is penetrated by the cutting instrument, 
and the latter may even break off and remain in the osseous tissue. 

Unlike punctures, cuts often involve the blood vessels and may 
give rise to hemorrhages. The hemorrhages are the more profuse the 
cleaner the incision is, the more firmly the vessel is fixed to the neigh- 
bouring parts, and, consequently, the less tendency it manifests to con- 
tract. In certain regions — e. g., in the neck — the veins being held open 
by the cervical aponeurosis, air may enter and produce accidents, which 
will be referred to in connection with gas emboli. 

When the cutting instrument incises a nerve we observe, in addition 
to the immediate pain, an anaesthesia or a paralysis affecting the region 



MECHANICAL AGENTS 19 

to which the nerve is distributed. These accidents are not incurable; 
for, on the one hand, the severed ends of the nerve may again be united, 
and, on the other, a functional supply is re-established through the 
agency of the numerous anastomoses connecting the various portions 
of the nervous system. 

When any one of the great cavities is incised, the wound, as in the 
case of punctures, may be nonpenetrating or penetrating, and in the 
latter instance it may be simple or complicated. Even though the 
wound does not involve any organ, it is much graver than a puncture, 
because it exposes the individual to a new accident, to hernia — i. e., the 
escape of the viscera. If the thorax is wounded, the lungs may pro- 
trude; if the abdomen is incised, the intestines and the omentum; at 
times the stomach, spleen, and bladder may escape. It is hardly neces- 
sary to say that such complications are of a grave nature, since they 
lead to contamination and infection of the protruded parts. 

When a limb is incised, the solution of continuity leads to modifica- 
tions, which must be well recognised, and which are explained by the 
contractility of the tissues. Suppose a limb is cut off in a plane per- 
pendicular to its long axis ; the resulting stump assumes the aspect of 
a cone the apex of which is represented by the bone and the base by the 
skin. This result is to be explained as follows : The bone is, of course, 
not displaced ; the deeper muscles adhering to the bone and retained in 
position by the aponeuroses have retracted very little; the superficial 
muscles, being more loosely attached, have retracted, and the skin, 
being far more contractile than the other tissues, has shrunken to a 
degree greater than all the subjacent parts. Therefore, in order to avoid 
a conical stump, it is necessary to incise the skin at a point farther 
down the limb than where the superficial muscles are severed, the latter 
farther down than the more deeply situated muscles, and the deeply 
laid muscles just beyond the cut end of the bone. 

In retracting, the muscles cause the cut ends of the tendons to recede 
into their sheaths, so that it is often difficult to bring their severed 
portions into contact. 

The contractility of tissues does not always act unfavourably. The 
contractility of the coats of the vessels plays an important part in 
hemostasis. When an artery is severed the external coat does not 
change its position; the middle coat, however, retracts, and in this 
manner diminishes the calibre of the vessel, thus favouring the forma- 
tion of an occluding clot. 

In other instances the contractility of the tissues hinders repara- 
tion. This is what happens when the trachea is incised. On transverse 
or even incomplete section of this structure the two lips of the wound 
retract, and this naturally prevents cicatrization. With the intestines 



20 INTRODUCTION TO THE STUDY OF MEDICINE 

the effects are similar but far graver, for the gaping of the wound 
permits the escape of faecal matter into the peritoneal cavity. 

When incisions are quite clean they very readily heal as soon as the 
separated parts are united and retained in position by sutures. It is 
then said that the wound heals by first intention. Such wounds, how- 
ever, may become infected and open a route for bacteria. Such an oc- 
currence is comparatively rare, for the clean-cut tissues preserve a very 
high degree of vitality and oppose the development of pathogenic 
agents, as when under normal conditions. Between what obtains 
here and in the case of contused wounds there is a very decided dif- 
ference. 

Contused Wounds. — Wounds caused by Firearms. — As already 
stated, the contusing agents are those which come in contact with our 
bodies by a blunt surface. 

Of contused wounds, the most interesting are those produced by 
firearms. Let us, therefore, begin with their study. After having indi- 
cated some general principles applicable to all firearms, we shall con- 
sider the effects caused by the new projectiles. 

In every wound caused by a bullet three parts are to be taken into 
consideration — namely, the point of entrance, the tract, and the point 
of exit. When the ball has lodged in the body there is evidently but one 
orifice, and the tract is therefore said to be blind. The wound at the 
point of entrance is always smaller than at the point of exit; it is 
even smaller than the diameter of the projectile. This phenomenon is 
due to the elasticity of the tissues. On the other hand, the aperture 
of exit is larger than the diameter of the ball; its diameter may be 
two to three times greater, and may attain to from 10 to 1.5 centimetres. 
The wound at the point of entrance is regular, with clean edges; the 
wound of exit is lacerated and often gives out particles of muscle and 
fragments and granules of bone. The tract of the bullet is direct or 
tortuous. It is direct when the missile is driven with great force 
through all the parts it encounters; it is tortuous when the speed of 
the bullet has been reduced and it ricochets over a bone. 

After having fractured a bone, a ball may impart to the fragments 
sufficient force to cause them to act as glancing missiles and aggravate 
the lesion by enlarging the wound. Fragments and granules of bone 
and particles of muscle are real foreign bodies, which must be eliminated 
in order to make cicatrization possible. The wound may also be con- 
taminated by solid substances, such as pieces of clothing, stones, and 
sand, which have been introduced from without. Moreover, the pro- 
jectile may lodge in the tissues ; it not infrequently breaks up, and each 
fragment then produces further disorganization in diverse directions; 
or a fragment may escape outward, thus leaving an aperture of exit 



MECHANICAL AGENTS 21 

and giving rise to the erroneous assumption that the projectile is no 
longer to be looked for in the wound. 

Bullets may produce three types of fractures in bones. In some 
instances the bone is simply perforated. If the cranium is the seat 
of injury there may be found two clean orifices, one corresponding to 
the point of entrance, the other to the point of exit of the projectile, 
the latter by far the larger. At other times the bone breaks by contact ; 
the fracture may be clean, as if cut with a sharp instrument; oftener 
it is comminuted — i. e., the fracture at times consists of a considerable 
number of fragments, or, as is frequently stated, of splinters. In 
higher degrees there is a true bursting of bone. Lastly, the third variety 
is produced when the bullet strikes the bone in a direction almost paral- 
lel to its long axis and cuts a veritable groove in the diaphysis. 

It is readily understood that a projectile moving at a low rate of 
speed, instead of breaking a bone, may lodge in it and flatten out; in 
other instances it may be diverted from its course, as is often the case 
when a revolver is discharged at close range at the thorax or the skull. 
Under such circumstances the bullet may follow a rib or a bone of the 
cranium without penetrating the cavity. In such instances it produces 
a subcutaneous " seton wound," which readily heals. 

Wounds of the arteries give rise to very grave hemorrhages. The 
statistics of the Crimean War show that in 18 out of 100 cases death 
was due to this cause. 

Finally, when a ball strikes an organ it may produce three varieties 
of lesions : a perforation, a laceration, or a crushing of tissue, which 
is then truly pulpified. 

Several hypotheses have been advanced to explain the action of 
projectiles. 

Melsens attributes an important role to the stratum of air which 
forms a kind of sheath around the ball, at least when its velocity exceeds 
340 metres. 

Kocher compares the resistance of tissues, particularly of bones 
with cavities containing marrow and blood, to that of a wooden barrel 
filled with liquid. If an empty barrel is shot at, the ball passes 
through, making simply two orifices ; if, however, the barrel is full of 
water, the energy transmitted to the incompressible liquid causes dis- 
ruption and bursting of the constituent parts. This conception unques- 
tionably contains a grain of truth and accounts for certain phenomena. 
But there is here no more than an accessory condition ; the real cause 
of the commotion caused by the projectiles depends upon their great 
velocity. The terrible effects of the arms of war are thus explained. 

The great revolution in military art by the introduction of organic 
explosives and powders has led to the transformation of armament and 



22 



INTRODUCTION TO THE STUDY OF MEDICINE 



to the utilization of projectiles of small calibre. The ball of the Chasse- 
pot and Gras rifles, which was formerly 11 millimetres in diameter, 
has been reduced to 8 millimetres; its weight also has been decreased 
from 25 to 15 grammes. On the other hand, the velocity has been 
increased. Instead of 450 metres the Lebel ball travels with an initial 
velocity of 631 metres per second. The rotary motion, which formerly 
amounted to 800 turns per second, is now 2,550. Since force depends 
upon velocity far more than upon weight, it will readily be understood 
that the Lebel ball, projected with a greater force, should be more 
effective. Its power is stated as 344.192 kilogrammetres, whereas in 
the Gras rifle it did not exceed 257.175 kilogrammetres. The truly 
active work accomplished — i. e., the coefficient of pressure per square 
millimetre — is three times greater: from 2.61 kilogrammetres it is 
raised to 6.847. 



Country. 


Model of rifle. 


Calibre. 


Weight 
of bullet. 


Length 
of bullet. 


Sheath of bullet. 


Speed 
at 25 m. 






mm. 


grammes. 


mm. 




metres. 




1886 


8 


15 


30 


German silver. 


600 


Germany . . 


Mauser-Mannlicher 

(1888) 


7.9 


14.7 


31.6 


Steel covered with 
German silver. 


620 


England. . . 


Lee-Medfort (1889). 


7.7 


14 


31.6 


Id. 


625 


Austria. . . . 


Mannlicher (1888). 


8 


15.8 


31.8 


Id. 


620 


Roumania. . 


Mannlicher (1892). 


6.5 


10.3 


31.4 


Steel covered 
with nickel. 


700 


Russia. . . . 


1891 


7.62 


10.86 


30.48 


German silver. 


615 


Switzerland 


Ruhin-Schmidt 
(1889) 


7.5 


13.7 


20 


Copper. 


600 



The great velocity of projectiles and the reduction of their calibre 
have necessitated a change in their construction. In order to avoid the 
fouling of the barrel of rifles with lead and to prevent alteration in their 
form, and also to assure greater penetration, it has been found neces- 
sary to use projectiles having a nucleus of lead guarded by a layer of 
German silver. They are ogival cylinders measuring 30 millimetres in 
length ; the anterior part, instead of tapering, bears the letter S. 

The various European countries have modified their armaments in 
the same direction as has France. The question having a certain 
amount of real interest, we present in tabular form on this page the 
particular features of the principal models. It will be seen that the 
differences are, on the whole, of little importance. 

The new projectiles were first experimented upon by Bruns, and later 
by Habart and Reger. These observers employed reduced charges and 
shot at cadavers placed at limited distances. They found that the pro- 
jectiles passed through the tissues and bone without being distorted 
or divided, and they never remained in the wound. They were, in fact, 
ideal projectiles of war; there seemed nothing to be done except to 



MECHANICAL AGENTS 23 

arrest bleeding and to close the wound, since there were no foreign bod- 
ies or splinters to be looked for. 

However, the researches of Chauvel and Mmier, Delorme and Cha- 
vasse, and Bogdanick led to less optimistic conclusions. The brilliant 
work of Demosthen conclusively established that the new projectiles are 
capable of producing fearful injuries, and his views were confirmed by 
von Coler and Schjerning, and by Labat. 

The difference in results is due to the fact that the first experiment- 
ers employed reduced charges. They were thus able to fix at will the 
speed of projection; but in reducing the charge they diminished the 
speed of rotation. Now, the latter remains almost constant through- 
out the entire flight of the projectile; it is decreased hardly any with 
distance. It is to this factor, therefore, that the injuries produced by 
the new firearms are largely to be attributed. 

Experimenting under actual conditions, it was recognised that, con- 
trary to the assertions of several authorities, the new projectiles were 
easily distorted and fractured. Delorme and Chavasse admit the fol- 
lowing classification in this respect : deformation of the point, lateral 
deformation, partial separation of the envelope, fragmentation with 
separation of the lead nucleus and of the envelope. These altera- 
tions may be produced on contact with bones, or when the ball rolls 
over after having struck a resistant plane, such as a gun, a piece of 
equipment, a carriage, or a wall. Thus deformed, a ball causes consid- 
erable damage and often lodges in the wound. 

Thus we find that all the lesions which the old arms produced are 
noted here. While the Chassepot projectiles cause no serious injury 
at 1,200 metres, the new projectiles are effective at more than 1,500 
metres ; at 2,000 metres their velocity is still 197 metres per second. In 
former days a ball exhausted its effects upon the object with which it 
came in contact. At the present day the projectile can penetrate six 
cadavers at the beginning of its flight ; at 1,500 metres it retains suffi- 
cient force to penetrate one. Finally, as Demosthen has shown, the 
lesions produced are not merely perforations. In the cranium a genu- 
ine shattering of the bones is induced ; in the bones of the limbs, even 
when the projectile is discharged at a distance of 1,500 metres, com- 
minuted fractures with 15 to 20 fragments are observed. Along the 
track of the missile the muscles are contused and mixed with fragments 
of osseous substance. It may be added that osseous fragments, receiv- 
ing a certain amount of energy from the ball, may inflict glancing blows 
to the tissues ; that cleanly cut vessels bleed to an alarming extent. If 
we remember that the effects are always less marked on the cadaver 
than on the living body, we arrive at the conclusion that the new pro- 
jectiles are capable of causing lesions incomparably more serious than 



24 INTRODUCTION TO THE STUDY OF MEDICINE 

the older types. It is then sad irony to designate as humane pro- 
jectiles those bullets whose field of action is of wider range and whose 
destructive power is so much more extensive ! 

Explosions. — It is useless to dwell upon the various conditions 
under which explosions take place. The ignition of illuminating gas, 
the bursting of a vapour or compressed-air engine, the explosion of fire 
damp, the ignition of substances employed in the industries or used for 
criminal purposes, such as fulminate of mercury, dynamite, picrate, 
acetylene, represent a series of well-known examples. 

The accidents produced by explosives are more complex than those 
caused by projectiles. Aside from the mechanical effects, the increase 
of pressure and the modification of temperature are to be considered. 
In some instances the temperature reaches 2,000° C. In other in- 
stances — for example, when an apparatus containing compressed air 
explodes — there results such a degree of cold as to induce death of the 
integument by freezing. Moreover, certain gases are deleterious, and to 
their mechanical and physical effects is added toxic action. 

The first result of an explosion is an increase of pressure. In the 
case of illuminating gas, a mixture with air of one sixth of its volume 
gives a pressure of 18 atmospheres in the open and 23 atmospheres in a 
closed room. With explosive substances the figures are far higher; 
fulminate of mercury exploded in its own volume gives a pressure of 
18,750 kilogrammes to the square centimetre! 

Under the influence of these enormous pressures, a person stationed 
within the dangerous zone is violently thrown and flattened against 
the walls. In order to avoid this accident in factories where explosives 
are handled, the shops are made of wood. In the event of an explosion, 
the feebly resistant walls give way, leaving a free passage for projected 
individuals. A second danger lies in the fall of walls and ceilings. 
But the most fearful accidents are those produced by dispersion of a 
multitude of small fragments of glass, wood, stone, and metal. 
Thrown with great force, these bodies, however minute, may cause ter- 
rible destruction. This is easily understood from the following two 
facts borrowed from Brouardel: 

An explosion occurring in a shop in Beranger Street, where ful- 
minate of mercury destined for the manufacture of children's toys was 
stored, destroyed fourteen lives. Among the victims was an individual 
whose abdomen and thorax were torn open; the intestines, lungs, and 
heart were as though they had been minced. These frightful lesions 
were simply due to the projection of pieces of pasteboard used in the 
manufacture of cartridges. The small foreign bodies had lacerated the 
viscera, and the force of penetration was such that several fragments' 
had entered the vertebral column to a depth of 4 to 5 millimetres. 



MECHANICAL AGENTS 25 

In the dynamite outrage which took place in the Boulevard Ma- 
genta, one of the victims received more than a thousand wounds pro- 
duced by sand, splinters of glass, and wood. Some idea of the force 
acquired by the minutest objects is given by the fact that in this same 
explosion a glass candlestick was found perforated through and 
through by a match. 

Finally, cartridges of dynamite sometimes explode in the hands of 
workmen in arsenals. In such instances the bones of the hand then act 
as so many projectiles which penetrate the abdomen or the thorax. In a 
case observed by Bouchard a finger nail was driven with sufficient force 
to penetrate the muscles of the thorax and pierce the lung. 

The various objects thus thrown are generally soiled with microbes, 
which may give rise to fatal infection. Thus, the man referred to in 
connection with the Magenta outrage died from the infections which 
developed in his wounds. 

Simple Contusions and Contused Wounds. — We now come to the 
consideration of the less terrible but more common agents of contusion. 
Let us note, for example, the effects produced by blows from a club, 
kicks of either man or animals, collapse of buildings, or falls. 

There may result a simple contusion or a contused wound. 

There is contusion when attrition of soft parts is produced without 
wound or fracture. 

There is a contused wound when the soft parts are torn. 

In bones, three kinds of fractures may be observed : 

1. Fracture at the point of application of the cause. For instance, 
when a traumatism — a blow of a club or a kick of a horse — breaks the 
bone at the point where it is struck. 

2. Fracture at a distance. Here a curvature of the bone occurs, 
which gives way at its point of least resistance. 

3. Fracture by contre-coup. A blow on the top of the skull, for 
example, causes a fracture at the base. 

These three .varieties of fractures may be observed when an indi- 
vidual falls on his heels. According to a multitude of concomitant 
conditions, a fracture of the calcaneum or of the leg, of the body or 
neck of the femur, of the pelvis, the spine, or the base of the skull 
may occur. 

If the wounding agent is less active it causes a simple fissure, at 
times but microscopic fissures. These lesions readily heal ; but they may 
be followed by persistent pain, and even by the development of hyper- 
ostoses as a result of too active reparative processes (G-ussenbauer). 

When a contusing body acts on the viscera, the lesions produced 
vary according to the resistance offered by the latter. In the case of the 
brain, the tissue is often reduced to a pulp ; in that of the liver or the 



26 INTRODUCTION TO THE STUDY OF MEDICINE 

spleen, simple or radiate fissures are produced, which are capable of 
giving rise to profuse hemorrhages. 

If the contusing agent strikes an organ provided with a thick cap- 
sule — e. g., the testicle — the effects differ. The experiments of Monod 
and Terrillon have shown that the testicle is capable of resisting great 
pressure. A force of 50 kilogrammes is required to burst its envel- 
ope, which then yields and ruptures abruptly. 

Notwithstanding all the injury inflicted by contusing agents, in 
most instances they do no more than dissociate the cells without de- 
stroying them. For this reason the bruised tissues, if transplanted 
beneath the skin of an animal, may retain their vitality and be ingrafted. 
(Gussenbauer), and this also explains why repair is so easily effected. 

When a hollow organ is subjected to slight contusion, nothing be- 
yond simple ecchymosis or a slight attrition of the walls occurs. In 
severe cases a rupture may take place. This accident generally results 
from compression of the organ between the wounding agent and some 
resistant part of the body — viz., a part of the skeleton. The kick of a 
horse perforates the intestine by pushing this organ against the spine ; 
it is this bone that produces the perforation. Likewise, in falls upon 
the perineum, rupture of the urethra is due to the pressure of the latter 
against the ischio-pubic branch of the pelvis. 

Finally, if an organ full of liquid is contused, it bursts ; such is par- 
ticularly the case with the bladder. 

Eupture of the blood vessels naturally gives rise to hemorrhages, 
which may occur either immediately or subsequently to the injury, 
in the form of simple ecchymoses or interstitial effusions; or they 
may take place inside of some visceral cavity. Interstitial hemorrhages, 
when profuse, give origin to genuine tumours — hematomata. These 
may be circumscribed or diffuse. While they are, as a rule, limited, they 
may subsequently increase in size. Moreover, they may often become the 
starting point of suppurations. 

In addition to effusions of blood, those of serum and oil are to be 
mentioned ; and if the traumatic focus communicates with the exterior 
or with a neighbouring organ, effusions of gas or organic liquids may 
occur. 

The secondary effects of contusions will be studied in another chap- 
ter. These are sphacelus and inflammation of the focus, and in some 
instances the formation of emboli in the diseased tissues. 

Commotion. — An interesting variety of contusion is represented by 
the phenomena described as commotion. Two principal varieties are 
admitted — cerebral and medullary commotion. They will be treated 
of in connection with nervous reactions. It may be noted here, how- 
ever, that the effects are in some instances accounted for by mechan- 



MECHANICAL AGENTS 27 

ical lesions. Under the influence of a blow dealt at the anterior part 
of the cranium, the cerebro-spinal fluid, being driven abruptly, pro- 
duces sufficient lesions in the floor of the fourth ventricle to explain 
the symptoms. 

Compression.— We have hitherto supposed that mechanical agents 
acted by sudden pressure, and that they were endowed with a great 
amount of energy. In other cases the morbific agent exerts a con- 
tinuous pressure, tending to diminish the bulk of the organs and to 
prevent their free expansion. Such a condition is spoken of as com- 
pression. 

Compression may be produced by tight clothing, notably by shoes. 
It is often connected with the occupation of the individual, and is then 
attended by friction. In other cases it may result from improper ad- 
justment of a surgical apparatus, or the use of crutches, etc. 

Compression may also result from the development or displacement 
of certain parts of the organism. The head of the foetus, when it rests 
too long in the parturient canal, may compress the nerves of the pelvis 
or the walls of the utero-vaginal canal. 

Fragments of splintered bone, effusion of blood, and tumours push 
away neighbouring parts and cause disturbances and alterations. 

The simplest cases are those in which the epidermis is compressed 
and becomes the seat of callosities. If a mucous membrane is com- 
pressed in a marked and persistent manner the result is an ulceration 
which may terminate in necrosis, gangrene, or perforation. In the 
case of a vein, compression produces a stasis, which is compensated 
by the development of a collateral circulation. The collateral circula- 
tion, however, is at times insufficient, and, as a consequence, oedema 
or, in very rare cases, even gangrene may appear. The latter is a far 
more frequent complication in those instances in which ischaemia results 
from compression of an artery — a state highly favourable to the devel- 
opment of microbes. 

Finally, compression may affect a nerve, as is sometimes the case 
where crutches are used. The same thing occurs when a person falls 
asleep while supporting his head with him arm. In this case the radial 
nerve is compressed by the head at the groove of torsion. Formication 
is first felt, then sensation diminishes and disappears, and finally move- 
ment becomes impossible. If compression has lasted but a short time 
the paralysis soon disappears, and sensation returns, preceded by quite 
painful formication. 

It is of importance to know these facts. Paralysis of the radial 
nerve was formerly attributed to the action of cold. It was said to 
occur when a person slept in the open air or with the window open. 
Dr. Panas has justly opposed this view. He has pointed out that paral- 



28 INTRODUCTION TO THE STUDY OF MEDICINE 

ysis does not attack the limb exposed to the air, but the one that is 
compressed by the head. 

Compression of the viscera by external agents is more rarely ob- 
served. We need but mention the effects produced by too tight belts 
and, above all, by corsets, which give rise to deformities of the stomach 
and liver. At autopsies it is not rare to find upon the surface of these 
organs the furrows which plainly show the impression left by the 
ribs pressed inward by the corset. The corset is even believed to play 
a part in displacement of the kidney. Eenal ectopy, which is observed 
chiefly in women, and nearly always upon the right side, is attributed 
to the action of the liver, which, being pushed by the corset, presses the 
kidney out of place. 

Mechanical Agents acting by Distention 

All those agents which we have thus far studied exert pressure. We 
shall presently consider those that act by distention. 

Disregarding distention of the esophagus by a too bulky bolus of 
food, and the therapeutic procedure employed in the treatment of a 
stricture by abrupt or progressive dilatation, we see that mechanical 
agents may act in two ways : In some cases the individual is fixed and 
the wounding agent tends to distend and to tear off a part of his body ; 
in other cases a part of the body is held motionless by the external 
agent and the individual causes distention by an abrupt movement. 
As principal illustrations it suffices here to refer to the severance of a 
limb from the body by a revolving wheel or a power belt or the jaws of 
an animal. There are instances on record in which limbs were torn 
off by the surgeon in the course of mechanical manoeuvres for reducing 
a luxation. 

When a limb is strongly stretched it becomes distended. The limit 
of extensibility being reached, a rupture is produced. The rupture, how- 
ever, does not occur simultaneously in all the tissues. The skin, by 
virtue of its elasticity, is almost the last to yield, the nerve trunks alone 
resisting longer. Separation having been effected, the tendons remain 
attached to the part torn off, carrying at their free ends some fragments 
of the muscles into which they were inserted. The ligaments behave 
in a manner similar to the tendons and separate the apophysis to which 
they were fixed. The muscles rupture at varying heights. According 
to Polaillon, the extensibility is overcome and then the relaxed muscle 
is torn. The majority of surgeons, however, are of the opinion that 
rupture occurs in consequence of a reflex contraction — i. e., the muscle 
ruptures itself. In regard to the skeleton, rupture sometimes takes 
place by separation of articulations ; at other times, especially when the 
cause has acted obliquely, a comminuted fracture is observed. 



MECHANICAL AGENTS 29 

It is a remarkable fact that wounds produced by distentions are not, 
as a rule, very painful and do not cause profuse hemorrhages. The 
latter phenomenon is explained as follows : The arteries being strongly 
distended, the inner and middle tunics are the first to give way; the 
outer coat becomes elongated and narrow, and when it breaks it be- 
comes twisted so as to obliterate the lumen of the vessel and prevent 
bleeding. 

A most interesting observation in this connection is recorded by 
Morand : A man employed in a mill was caught by a power belt and his 
arm torn off. The enormous wound thus inflicted was attended by 
hardly any hemorrhage, so that he was able to walk to and consult 
a physician. He recovered in two months. 

As already stated, nervous tissue resists to a high degree. In cer- 
tain instances a severed limb is held only by the nerve trunks. The lat- 
ter, before rupturing, admit of considerable elongation. The median 
and ulnar nerves may be stretched to an additional length of 15 to 20 
centimetres. The results of Tillaux and Trombetta demonstrated the 
fact that very great force is required to rupture a nerve. On the cada- 
ver it is possible to raise the entire body by pulling the sciatic. From 
50 (Tillaux) to 84 kilogrammes (Trombetta) are required to cause 
rupture. 

Even for less voluminous nerves considerable traction is requisite 
before rupture occurs — 38 kilogrammes for the median, from 20 to 25 
for the ulnar, and for a little filament like the supraorbital nerve 2.5 
kilogrammes. 

Eupture does not occur at the point of application of the force. It 
is generally produced at the points of flexion. In the sciatic, for exam- 
ple, it occurs behind the ischium. In some cases the roots themselves 
are torn and detached from the spinal cord. 

Eesistance and Eeaction of the Organism 

In studying the mechanical agents, two factors are always to be 
taken into account — namely, the action of the wounding body, the 
importance of which we have sufficiently shown, and the resistance of 
the organism, which will now be considered in a few words. 

Since the human body is a nonhomogeneous structure susceptible 
to numerous reactions, and notably to muscular contractions, which 
modify the effects of resistance, the problem is quite a difficult one. 
There are, however, certain influences which have been well determined. 
One is the age of the subject. Under similar given conditions chil- 
dren resist better than adults, and the latter better than the aged. 
In children, very energetic causes are necessary to produce marked dis- 
turbances and fractures. The incomplete ossification and the flexibility 



30 INTRODUCTION TO THE STUDY OF MEDICINE 

of the bones explain their great resistance, as evidenced by the fact that 
a child may fall from a very great height without harm. On the other 
hand, in the aged the bones are rarefied and brittle. They are affected 
by what is called osteoporosis, and on the slightest cause they break. 
An abrupt movement in bed may cause a fracture of the neck of the 
femur, or a paroxysm of coughing may provoke a fracture of the ribs. 

The resistance of the blood vessels is no less variable. In women, 
the slightest shocks are often sufficient to give rise to ecchymoses. Cer- 
tain subjects, affected by a morbid state called hemophilia, have very 
grave hemorrhages from the slightest abrasion. Finally, arteriosclero- 
sis, by diminishing the elasticity of the arteries, favours their rupture. 
In this connection may be mentioned aortic insufficiency caused by a 
blow on the thorax; the sigmoid valves rupture because they were 
already diseased. 

Such illustrations might easily be multiplied, but these are sufficient 
to indicate the influence exercised by previous organic lesions upon the 
effects of traumatic agents. 

General Reactions. — In addition to local lesions, we must take 
into consideration the general manifestations occasioned by traumatism 
— namely, the various reactions in distant parts. 

The question whether a traumatic lesion can give rise to fever has 
of late been a matter of much discussion. After numerous experi- 
mental researches, the question seems to have been solved in the affirma- 
tive. Aseptic fevers are slight and transitory. Whenever the febrile 
movement is continuous, we should always look for some complication 
of an infectious nature. 

Wounds attended by great mortification of tissues and extensive 
contusion are especially liable to invasion by microbes. The clean-cut 
wounds — for example, those produced by sharp instruments — are less 
frequently subject to infection. This is not due to the fact that the 
bacteria do not contaminate them, but, on the contrary, the tissues 
possess sufficient vitality to oppose their development and prevent their 
multiplication. 

In a great number of subjects traumatic lesions give rise to intense 
nervous reactions, agitations, and delirium, and when violent may bring 
about a very grave and often fatal morbid complication — namely, nerv- 
ous shock. Aside from these transitory disturbances, a series of perma- 
nent affections may appear. Hysteria and, more rarely, chorea and 
paralysis agitans have been produced in predisposed subjects by even 
slight traumatism. These disorders of external origin, as has just 
been indicated, may be transmitted by heredity. In this connection 
nothing is more interesting than the classic experiment of Brown- 
Sequard. The great physiologist severed the sciatic nerve in a guinea 



MECHANICAL AGENTS 31 

pig ; this traumatism gave rise to epileptiform convulsions, which were 
transmitted to the offspring. 

In certain cases traumatism may be followed by permanent dis- 
orders, especially when nerves are involved. We here refer to trophic 
disorders, such as keloids, periostoses, exostoses, glistening state of the 
skin, small ulcers called by W. Mitchell causalgia, or nervous disturb- 
ances, such as neuralgia and painful cicatrices. In other cases trau- 
matism proves to be an occasional cause of morbid localizations. In 
consequence of a blow upon the toe a paroxysm of gout may be observed, 
or perhaps a microbic localization, or even the development of a neo- 
plasm. Max Schuller's classical experiment is well known. He inocu- 
lated tuberculosis beneath the skin of a guinea pig. At the same time 
a traumatism was produced at the knee. The pathogenic agent migrated 
to the wounded joint, and there gave rise to the formation of white 
swelling — tumor alius. Such facts are daily observed in clinics. 
Tubercular arthritis and meningitis are often referable to traumatic 
causes. Perroud observed in the boatmen of the Ehone a unilateral 
tuberculosis, the localization of which is due to the fact that these 
men propel the boats by means of a long pole which they press against 
one of their clavicles. 

Influence of Passive Movements. — We have hitherto supposed that 
mechanical agents tended to modify the situation of a part of our 
bodies. The result is a sort of conflict the consequences of which we 
have already considered. In many cases a mechanical agent displaces 
the subject entirely, and, by a movement passively transmitted, it 
carries him into space. If the displaced individual finds himself in a 
locality absolutely inclosed and endowed with uniform motion, and if all 
the surrounding objects move with him, he will not be conscious of 
movement and will not present any physiological or pathological reac- 
tion. In fact, it is easy to understand that we perceive our displace- 
ment through the changes occurring in our relations to the surrounding 
objects or our situation toward them. 

When we undergo passive movement, a series of manifestations 
occur around us which, if slight, make us aware simply of our dis- 
placement; but when they are intense they give rise to pathological 
phenomena. The first of these consists in variations of the blood 
circulation. By virtue of centrifugal force the blood tends to move 
in a reverse order to the movement which we undergo. The changes 
occurring in the circulation can be perceived through the peculiar sen- 
sation which we experience when the movement suddenly ceases — for 
example, when a train suddenly stops under the influence of the air 
brake. No matter how perfectly the vehicle may be equipped with 
devices to avoid jarring, the adjustment is never so complete as to secure 



32 INTRODUCTION TO THE STUDY OF MEDICINE 

us against all agitation. Here is a new cause of disturbance. Serious 
disorders may at last appear, as in the case with railroad employees, 
particularly engineers. However, the agitation may also produce 
some favourable results. Patients suffering from paralysis agitans 
have often been improved by travelling or riding in automobile car- 
riages. Impressed with this fact, Charcot conceived the idea of apply- 
ing agitation or commotion to the treatment of this neurosis. 

It is a matter of common observation that great oscillations, even 
when rhythmical, may occasion nervous disturbances. Such is the 
case with the swing. The dizziness resulting from its use is due to 
numerous causes. At each oscillation the centrifugal force tends to 
modify the circulatory hydraulics; the resistance of the air produces 
excitation in the mucous membranes and the skin; the displacement 
of objects acts upon the organs of vision; and, lastly, changes in the 
fluid of the labyrinth take place which affect the semicircular canals. 
Since the observations of Flourens and Cyon, it is known that an 
important part is played by this portion of the internal ear in equili- 
bration. 

An analogous mechanism serves to explain one of the most inter- 
esting disturbances of this order — namely, seasickness. In this case, 
however, the phenomena are more complex, since they are of a com- 
bined nature. We must take into consideration the oscillations of the 
vessel from side to side as well as those from stem to stern, and, in the 
case of steamers, to these must be added the vibrations produced by the 
engines. The results are disturbances of a sensitivo-sensory nature, 
modifications of the circulation, and displacement of the abdominal 
viscera. It is to the latter factor that the majority of authors attribute 
the most important role in the production of the manifestations. The 
visual disturbances, secondary though they be, should not be ignored, 
for it is often possible to avoid seasickness by fixing the vision upon 
distant objects. Objects that are constantly in motion should not be 
looked at. It is a well-known fact that when at rest we may experience 
malaise and dizziness by simply fixing our eyes upon moving objects. 
This, however, is only an auxiliary cause, since an individual may suffer 
from seasickness while the eyes are closed, and, moreover, the blind 
are not exempt from it. 

The influence of visual excitation upon the causation of dizziness 
is also made manifest when the gaze is fixed upon the water or ground 
over which we move while riding on a river boat, in a carriage, or train. 
Yet, contrary to what would naturally be expected, no dizziness is expe- 
rienced during the ascent of a balloon, no matter from what point the 
aeronaut may look. 

In conclusion, it should be borne in mind that mechanical agents 



MECHANICAL AGENTS 33 

may serve to fix us in a determined position. They then oppose our 
movements, and thus cause death. When, for example, an individual 
is caught in the ruins of a building, the debits resting upon him prevents 
the movements of the thorax, and thus causes asphyxia. In other in- 
stances mechanical agents fix the body in such positions as to com- 
pletely modify the circulation. The human subject bears these changes 
fairly well, and, except when the head is placed too low, the circulation 
is carried on in a normal manner. In animals adaptation is not so 
readily accomplished ; an animal fixed vertically soon dies from cerebral 
ansemia, since the heart is unable to cope with gravity and to send to 
the nerve centres a sufficient amount of blood. 



CHAPTER III 
PHYSICAL AGENTS 

Atmospheric pressure — Influence of its variations — Mountain sickness — Altitude 
cure — Heat — Burns — Heat stroke and sunstroke — Cold — Frostbites — Light, its 
local and general effects — Braidism — Sound — Electricity — Physiological action 
of currents — Fulguration and sideration — Electrocution — Practical applica- 
tions of electricity. 

Physical agents represent different forms of energy; they are five 
in number : atmospheric pressure, heat, light, sound, and electricity. 

Atmospheric Pressure 

The air exerts upon the earth a pressure of 1.03 kilogramme per 
square centimetre, or a total pressure of 18,000 kilogrammes for the 
human body. We are able to support this enormous pressure only 
because it is distributed in a uniform manner. 

The variations of atmospheric pressure can influence our state of 
health. When they are large and abrupt, and especially when rapid 
depressions of the barometer take place, nervous disturbances are ob- 
served in certain subjects, constituting barometric neurosis. Doubtless 
this expression is not perfect. Along with the variations of pressure, 
there occur changes in temperature, in humidity, in the solar radiations, 
and in the direction of winds which must play a part in the final 
result. Nevertheless, the barometric disturbances are most easily ap- 
preciable and have served to designate the morbid manifestations. The 
same influences may intervene to modify the resistance of living beings 
to infectious agents ; they explain the development of seasonal maladies 
and play an important part in what is called the epidemic temperament 
(le genie epidemique). 

In order to distinguish the influence of atmospheric pressure from 
other factors, it is necessary to consider what takes place when climbing 
a mountain or making a balloon ascent. Such a study has a double 
interest: through the serious accidents which it brings to our knowl- 
edge, it gives us an idea of the beneficial effects of a sojourn in high 
regions and of the mechanism of altitude cures. 
34 



PHYSICAL AGENTS 



35 



It is a well-known fact that during an ascent the pressure decreases. 
The following figures, taken from the remarkable work of Kegnard, 
give an idea of the variation of pressure with altitude. The sea level, 
upon which there is a pressure of 76 centimetres of mercury, is taken 
as a standard. 



The sea 

Orthez 

Aigle-Bains 

Chamounix 

St. Bernard 

The observatory of Mont Blanc 

The pass of Parang (the highest point habit- 
ually visited by man) 

Mount Everest (the highest point of the globe) 

The ascents of Croce-Spinelli and Sivel 

The ascents of Glaisher 



Barometric height. 


Altitude (in metres). 


76 





75 


105 


71 


540 


67 


1,050 


56 


2,370 


42 


4,810 


37 


5,835 


24.8 


8,840 


26 


8,600 


24.8 


8,838 



In ascending in the atmosphere a number of disturbances are expe- 
rienced which may prove fatal. 

It is an error to attribute these symptoms to modifications in the 
constitution of the atmosphere. Whatever the altitude, the composition 
of the air is always the same ; it always consists of 21 parts of oxygen, 
78.06 of nitrogen, and 0.94 of argon. By means of a balloon sound Cail- 
letet, the aerophile, was able to collect a sample of air at a height of 
15,500 metres. The anlysis made by Muntz and Schloesing, Jr., gave 
20.79 parts of oxygen, 78.27 of nitrogen, 0.94 of argon, and 0.0033 of 
carbonic acid. The somewhat low figure for oxygen is explained by the 
conditions of the experiment — a small quantity of this gas was absorbed 
by the copper plugs and by the oxidizable grease used to facilitate their 
working. 

The only modification of the air in high regions is a notable in- 
crease in ozone; and this possibly is the explanation of certain thera- 
peutic effects. A recent analysis made by Maurice de Thierry makes 
the variations of this gas quite evident : At the same hour of the same 
day, air gathered at Paris yielded 2.3 milligrammes of ozone; at Cha- 
mounix (1,050 metres) it yielded 3.5 milligrammes; and, finally, at 
Grands Mulets, on the slope of Mont Blanc (3,020 metres), 9.4 milli- 
grammes. 

Since the variations in the chemical composition of the air do not 
explain the harmful effects of altitudes, let us consider other modifica- 
tions which take place on mountains. 

There is, in the first place, a fall in the temperature. It is regarded 
as a law that the temperature diminishes one degree centigrade for each 
rise of 160 metres, a figure which may be retained, although it may not 



36 INTRODUCTION TO THE STUDY OF MEDICINE 

be very exact. Cailletet's apparatus indicated, at a height of 15,500 
metres, a temperature of — 60°, while the calculation gave — 83° C. 

What is of greater importance from a medical standpoint is that 
the cold is quite tolerable in high regions. This result is for the most 
part due to the action of the sun's rays, which strike more perpendicu- 
larly than on the plain; and this explains also the considerable differ- 
ences which are obtained according as the temperature is taken in the 
shade or in the sun. At Davos, for instance, which is situated at an 
altitude of 1,560 metres, and is a winter resort for many consumptives, it 
is not unusual to observe the thermometer stand at — 5° C. in the shade 
and -f- 12° C. in the sun. If the bulb be covered with blackened cotton, 
in order to prevent radiation, the thermometer records + 30° C. There 
is then a difference of 35° C. between localities exposed to the sun and 
those lying in the shade. 

The snow, however, does not melt, because the air does not grow 
warm and the rays of the sun are all reflected by the white surface, 
which acts as a perfect mirror. The proof of this is that if the surface 
of the snow be covered with a black body, such as a simple dead leaf, 
the snow melts at that point, because a storing up of heat rays occurs 
there. Our clothes play the same part; they retain the heat and pre- 
vent us from feeling the cold, even on the snow. 

Again, another condition favourable to life without suffering in 
high regions is the absence of wind and humidity. 

Mountain air is so dry that putrefaction does not occur. In the 
Valais, for example, when it is desired to preserve eatables, they are 
exposed to the sun without being salted. Desiccation is effected before 
putrefaction can set in. At St. Bernard the corpses of men and ani- 
mals never decay, and, as it is impossible to dig graves in the rocky 
soil where the monastery is situated, they are placed in a morgue, where 
they are preserved indefinitely. 

The rarefaction of the air explains also a phenomenon which often 
causes irritation to patients — namely, the absence of noise. No sound 
is heard among the mountains because the air is no longer dense enough 
to transmit it; this phenomenon makes so vivid an impression upon 
certain persons that it produces a deep feeling of sadness. 

Let us now consider the therapeutic effects of altitudes, and let us 
first study the influence of moderate altitudes. 

Suppose, for example, a man who undertakes to receive, for thera- 
peutic purposes, an air cure on a mountain from 2,000 to 4,000 
metres high. What will be the results ? Having arrived at the locality 
where he is to stay, that man will pass through a first period, that 
of acclimation ; he will first feel a warmth quite noticeable on his skin. 
His lips will be redder than in the normal state and his conjunctivae 



PHYSICAL AGENTS 37 

flushed. For two or three days he will have insomnia; he will occa- 
sionally experience palpitation, dyspnoea, dizziness, and, more rarely, 
headache. The urine is dark, constipation is the rule, and, finally, from 
the start, appetite is increased. 

These first phenomena last for a week. At the end of this period 
the man is acclimated. The external appearance is changed; the skin 
assumes a tan colour ; the integuments and hair are so dry that poma- 
tum or vaseline must be used. The appetite has further increased, as 
has also the muscular strength, and the longest walks do not produce 
fatigue. 

When afterward he comes down to the plain the skin becomes warm, 
burning, it splits and peels, but the favourable manifestations persist; 
the strength and appetite remain increased, at least for some time. 

Mountain Sickness. — If we consider the effects of great altitudes, 
we find a series of disturbances which are collectively called mountain 
sickness. It is frequent at an elevation of 3,000 metres, but at 4,000 
it is almost unavoidable. But it does not occur equally in all countries ; 
it is more common in the Alps than in the Andes and the Himalayas. 
In Mexico an ascent of 4,000 metres may be made without incurring 
any sickness. Jourdanet reports that in the Andes villages may be 
seen at heights greater than 3,000 metres. On the basis of these facts, 
it has been stated that the higher the zone of perpetual snow the slower 
are the symptoms. In fact, cold is one of the principal elements in the 
genesis of the disturbances. 

All climbers are not equally subject to mountain sickness. Train- 
ing and temperament must always be taken into account. The 
quicker the ascent the greater the risk of being affected. If the ascent 
is made slowly, by short stages, acclimation is more readily effected. 
By repeating the ascents, the climber becomes proof against symp- 
toms which a beginner can seldom escape. It is, however, important 
to know that the experience of the same person may be quite different 
in two successive journeys. An explanation of this fact is often found 
in his physical condition. When the evening repast has been poorly 
digested; when the sleep has been insufficient, agitated, disturbed, or 
interrupted, mountain sickness is likely to occur. The guides are not 
deceived in that respect, and from the appearance of the climber they 
predict to him how he will come out of his excursion. Indeed, fatigue 
is one of the most important factors, and this explains why mountain 
sickness is more common among climbers than among aeronauts. 

The symptoms characteristic of mountain sickness are quite analo- 
gous to those of seasickness. The first phenomenon is a feeling of gen- 
eral weakness ; the person has pains in the lower extremities, especially 
in the knees; soon saliva comes in great abundance into the mouth; 



38 INTRODUCTION TO THE STUDY OF MEDICINE 

then nausea is felt, followed by alimentary vomiting, and, in grave cases, 
bilious and hemorrhagic vomiting. At a more advanced stage, the 
person has colic and diarrhoea ; at the same time his body becomes cov- 
ered with cold sweat. If he is examined at this moment his respiration 
is found to be very rapid, and the pulse irregular, rapid, and feeble. 

If the person continues his ascent, he feels worse; dizziness, daz- 
zling, humming in the ears, and a violent headache supervene. He 
falls into a state of indifference, an absolute apathy. He asks to be left 
undisturbed; he is not able to walk, his will is completely annihilated. 
He can not resist an invincible desire to fall asleep. In serious cases 
all movement soon becomes impossible, and profound exhaustion is 
produced, which terminates in death. 

Many hypotheses have been proposed to account for mountain 
sickness; it has been attributed to the changes in the constitution of 
the air, but we have seen that this explanation is contrary to the facts ; 
and it has been ascribed to an action comparable to that of cupping, 
which is also absolutely untrue. 

The true theory, or at least the one that is to-day generally accepted 
as true, was put forward by Jourdanet and advocated by Paul Bert 
and by Regnard. According to these authors, mountain sickness is due 
simply to the rarefaction of the air — that is, the diminution of oxygen. 
There is, according to Jourdanet ? s expression, a barometric disoxygena- 
tion. Paul Bert made several very important experiments on this sub- 
ject. He first submitted to analysis the blood taken from animals 
which had been kept in rarefied air. He observed that the quantity 
of the oxygen in the blood diminishes as the atmospheric pressure is 
lessened. If the rarefaction corresponds to the pressure existing at 
2,000 metres of altitude, the oxygen diminishes 13 per cent; at 3,000, 
21 per cent ; at 6,500, 43 per cent ; and at 8,500, 50 per cent. It is this 
lack of oxygen that causes death. In fact, if, as the air is rarefied, the 
proportion of oxygen in it be increased, the animal does not succumb ; 
it does live at a low pressure, provided the air be supplied with a suffi- 
cient amount of oxygen. 

Starting from this principle, Paul Bert experimented upon him- 
self. He inclosed himself in a large bell in company with a bird 
and a rat. The air was gradually rarefied ; the pressure fell to 24 centi- 
metres, realizing the condition at the highest summit of the globe, at a 
height of 8,800 metres. Under these conditions the bird and the rat 
succumbed. Paul Bert himself was allowed, by a special contrivance, 
to breathe super oxygenated air; in that way he experienced no disturb- 
ance, but as soon as he tried to breathe the rarefied air in the bell, 
symptoms were manifested which disappeared under the influence of 
oxygen. 



PHYSICAL AGENTS 



39 



Croce-Spinelli, who witnessed the experiment, hoped to profit by it. 
In a balloon ascent which he made a few days later with Sivel he rose 
to a height of 8,600 metres. The aeronauts had taken with them re- 
ceivers full of oxygen, but when about to make use of them, paralyzed 
by the cold and exhausted by altitude sickness, they were unable to 
reach their apparatus, and succumbed under the same conditions of 
aeration as those under which Paul Bert had survived. 

The theory just expounded explains perfectly why one can resist 
better in making a balloon ascent than in climbing up a mountain ; for 
in the latter case the muscular exertion, which is inevitable, requires 
the consumption of a considerable amount of oxygen to provide for 
the more active oxidation ; therefore the effects produced by the diminu- 
tion of this gas are felt much more rapidly. 

Along with this principal factor we must take into consideration 
certain other conditions. The surrounding air being rarefied, intestinal 
gases expand and produce tympanites. At the same time the blood 
rushes toward the skin, and from this results anaemia of the internal 
organs. But it is quite certain that these diverse disorders play an 
altogether accessory part. 

Acclimation and Altitude Cure. — When a person remains for a 
while on the mountains, three kinds of modifications take place in 
his blood; an increase in the capacity for absorbing oxygen, an 
increase in the number of red corpuscles, and an increase in the iron 
content. 

Among the experiments upon which the foregoing conclusions are 
based we must cite those of M. Muntz, who operated on rabbits of 
the same brood, some of which had been left on the plain and others 
transported to the mountain, to the Pic du Midi. At the end of seven 
years, M. Muntz analyzed the blood of these two classes of animals, or 
rather of their descendants. M. Eegnard made a similar experiment on 
guinea pigs. Instead of transporting some of them to a mountain, 
however, he made them live in rarefied air having the same pressure 
as at an elevation of 3,000 metres; the experiment lasted one 
month. Finally, M. Viault applied himself to the study of the red 
corpuscles, which he counted in the animals which had been transported, 
like those of Muntz, to the Pic du Midi. 
Here are the results obtained : 



Animals U n ^ e P^ a . in li V' 
( On the heights. 



Oxygen absorbed in 
100 grammes of blood. 



Cubic centimetres. 
Muntz. Regnard. 

9.56 14 

17.28 21 



Iron contained 

in 100 grammes 

of blood. 



Milligrammes. 

Muntz. 

40.5 

70.2 



Corpuscles in 1 cubic 
milligramme of blood. 



Yiault. 
4.000.000 to 5,000.000 
6,000,000 to 7,000,000 



40 INTRODUCTION TO THE STUDY OF MEDICINE 

These figures, which are in satisfactory agreement, possess great 
practical interest and fully justify the use of altitude cures for those 
suffering from anaemia, and especially chlorosis. A sojourn in the 
mountains is the best means of modifying the blood, increasing its 
richness in red corpuscles and iron, and heightening its power of 
oxidation. 

Increase of Pressure. — Like the diminutions, the increases in pres- 
sure are an interesting subject to study, on account of the symptoms 
they cause and the therapeutic effects they produce. Workmen who 
labour under water, whether for the purpose of gathering sponges, 
pearls, or corals, or laying the foundation of a bridge, find themselves 
in receivers in which the air is compressed to two or sometimes three 
atmospheres. The first phenomena consist of buzzing in the ears, due 
to the difference of pressure between the two surfaces of the tym- 
panum; in the cavity of the tympanum the air but slowly attains the 
same pressure as in the exterior. The difference may be sufficiently 
great to cause rupture of the membrane of the tympanum; therefore 
individuals who have a catarrh in the Eustachian tube should be cau- 
tioned against remaining in compressed air. 

At the same time a slackening and sometimes an irregularity in the 
respiratory movements are observed. The pulse, at first rapid, grows 
slow. Finally, the urinary secretion is notably increased. 

All these phenomena are on the whole quite harmless. The grave 
symptoms occur at the moment when pressure is removed; the more 
rapidly this is done the more frequent the manifestations become. 
When these appear it is sufficient, in order to stop them, to compress 
some more air into the receiver, and afterward to reduce the pressure 
gradually. The pressure at the outside diminishing, while it remains 
increased in the cavity of the tympanum, it is readily understood that, 
by a mechanism diametrically opposed, auditory disorders occur as be- 
fore. The person experiences buzzing in the ear; in certain cases the 
symptoms go further: hemorrhage results and the membrane of the 
tympanum may rupture. At other times the subjects complain of 
great fatigue and a tendency to fainting. If the reduction of the 
pressure is rapid, blood flows from the nose, ears, and lungs. On the 
skin, little punctiform hemorrhages will develop, which workmen des- 
ignate under the expressive term of flea bites (puces). In serious cases 
paralysis may be observed, which generally attacks the lower extrem- 
ities, often reaching the bladder and rectum, and which, if it lasts over 
forty-eight hours, may be regarded as almost incurable. Finally, a 
still more rapid reduction of the pressure may cause sudden death. 

These various phenomena are readily explained on making an 
autopsy. All the vessels are filled with gas bubbles, because during 



PHYSICAL AGENTS 41 

compression the nitrogen is in great quantity dissolved in the blood; 
on reduction of the pressure, if effected slowly, the nitrogen is grad- 
ually eliminated by the lungs; if the pressure be reduced rapidly, the 
abrupt changes in external pressure cause the liberation of the gas, 
the bubbles of which obstruct the vessels and arrest the operation of the 
heart, lungs, brain, medulla, and the pons. 

The great variations of pressure occurring in case of explosion 
explain certain mechanical phenomena, and particularly the projection 
of small objects which, by their kinetic energy, cause more serious 
accidents. The increase of pressure, which sometimes does not exceed 
20 atmospheres, may reach 1,500. But at the moment explosion 
takes place it first makes a depression that is an almost absolute 
vacuum around the victims; this is why they are shorn of their 
clothes. The air gathered between the clothes and the body expands 
and tears the clothes to pieces. Only such articles as shoes, garters, 
and corsets, which stick close to the body, may remain. 

Heat 

Heat may act on the entire person, or on a portion of the body, in 
which latter case it may cause a burn. 

In a general way, we may say that heat is not so well endured as 
cold. It is sufficient that the surrounding temperature rise to 40° C. 
for us to feel uncomfortable; we suffer from this temperature, which 
is 3° above that of our bodies ; while the low temperatures of — 10° C. 
and — 15° C. — that is, from 47° to 52° below the temperature of our 
bodies — produce no inconvenience. 

It is true that life may be maintained in countries where the tem- 
perature reaches, as in Senegal, 50° or 53° C, but it must be acknowl- 
edged that acclimation is there quite difficult. The majority of Euro- 
peans who emigrate to those regions succumb ; their children pine and 
the race becomes extinct. On the contrary, in the case of emigration to 
cold countries, the organism easily adapts itself to the new conditions. 

The differences are similar when we consider the variations of ani- 
mal heat. When our bodily temperature rises 4° or 5° C, the situation 
is regarded as very serious, and survival is quite exceptional after 43° 
in the rectum is reached. Diminution of temperature is, on the con- 
trary, much better endured, and it has been observed that animals 
readily recover after their temperature has been reduced, by abstraction 
of heat, to 20° and even 16° C. 

We are not to believe, however, that we are unable to stand heat at 
a high temperature. It is possible to live in places having a tempera- 
ture of 100° C. Blagden entered an oven showing 129° C, and staid 
there nine minutes. 



42 INTRODUCTION TO THE STUDY OF MEDICINE 

The organism is able to resist these high temperatures because it 
possesses several means of protection. 

In the first place, internal combustion diminishes. Then the vessels 
dilate, and the blood rushes to the surface of the skin, and this facili- 
tates the loss of heat. Finally, and this third mode of resistance is 
the most important, sweating sets in and the evaporation of the secreted 
liquid produces a notable cooling effect. This is why dry heat can be 
endured much better than humid heat. 

In those animals which do not perspire, such as the dog, evaporation 
takes place through the mouth; the animal puts out its tongue and 
executes rapid respiratory movements. If, as was done by Eichet, the 
evaporation of the liquid is prevented by tightly muzzling the mouth, 
the animal succumbs to heat stroke; but the control, which breathes 
freely, resists. 

For a systematic study of heat, we must successively consider its 
local and general effects. . 

Burns. — The local effects of heat are called burns and scalds. 
These may be produced by radiation, as is occasionally observed in cer- 
tain trades, among glass blowers, for example. More often they are 
produced by contact with a hot body, liquid or solid. If it is a gas, the 
burns are superficial but extensive, and we shall presently see that the 
extent is of greater consequence than the depth. If it is a liquid, the 
scalds are deeper. Their extent varies according to circumstances. 
They may affect the entire skin of a person who falls into a vat of boil- 
ing liquid. A circumstance often increasing the seriousness of these 
scalds is that the clothes are impregnated with the burning liquid and 
prolong the action. In certain cases the phenomena of calefaction 
hinder the action of the liquid' body ; hence the possibility of plunging 
the hand or the arm, without inconvenience, into molten metal at a 
temperature of 1,000° C. 

The burns produced by solid bodies are, in general, very deep, but 
limited, and consequently less serious. 

In order to have an accurate idea of the effects of burns, we shall 
recall the well-known experiments of Cohnheim. This author plunged 
the ear of a rabbit into hot water. He states that a temperature of 42° 
or 44° C. produces but a transitory hyperemia. At 48° or 49° C, the 
ear tumefies ; oedema is produced. At 50° to 52° C, from the effusion 
of serum beneath the cuticle, blisters appear. At 56° to 60° C, gan- 
grene of the ear sets in. Similar results are observed in man and allow 
us to separate burns into a certain number of categories or degrees. 

It is usual, since Dupuytren, to admit six degrees of burns. 

The first degree is erythema; this is a simple redness of the skin,' 
produced under the influence of the radiant heat of a gas, of a liquid, 



PHYSICAL AGENTS 43 

or of a solid whose temperature is not very high. In certain workmen, 
in glass blowers, for example, the erythema may assume a chronic char- 
acter ; the skin thickens and splits on the face and hands. 

In the second degree the skin rises in blisters filled with serum. 

In both cases the lesions are superficial; they usually heal without 
leaving any traces. Nevertheless, especially as a result of blisters, a 
certain indelible pigmentation may persist. 

The remaining four degrees differ from the preceding in that they 
are attended by the destruction of the parts and give rise to the forma- 
tion of cicatrices. 

In the third degree the epidermis is disorganized and the mucous 
layer of Malpighi is reached. 

In the fourth degree the destruction of the skin is complete. 

In the fifth degree black masses are formed, involving soft parts to 
a greater or less depth. Finally, the sixth degree is reached, when the 
whole thickness of a limb is carbonized. 

The extent is of far greater importance than the depth. If limited, 
a burn of the fourth, or even of the fifth degree is not serious ; while a 
burn or a scald of the first degree may be fatal if it covers the entire 
skin. A person who falls into a vat of hot water and is immediately 
drawn out presents cutaneous lesions in appearance harmless, but he 
will succumb from the development of general manifestations. These 
differ entirely in their mechanism and symptoms, according as they 
appear soon after the accident or tardily. 

The immediate general phenomena are manifested in the following 
manner : 

There is, in the first place, a rise of temperature, which is explained 
by the application of heat; then, little by little, the temperature de- 
scends, falls below the normal, and may become very low. The respira- 
tion is slow, superficial, irregular, often intermittent with long pauses. 
The pulse is small, feeble, slow. Finally, the victim, indifferent to 
everything, falls into a comatose state, and succumbs with a progressive 
depression of the temperature. 

These immediate consequences are observed especially in cases of 
extensive and superficial burns. The remote phenomena are met with 
when the lesions are deep. 

The urine contains hemoglobin as the result of the breaking up of 
the red corpuscles. Sometimes hemorrhages occur, which are espe- 
cially marked in the intestines and lungs. At the autopsy, nephritis 
and duodenal ulcerations are found, the former of which, at least, suf- 
fices to account for death. 

The early symptoms are reflex manifestations, produced by the too 
violent excitation of the nerve endings ; it is a variety of nervous shock. 



44 INTRODUCTION TO THE STUDY OF MEDICINE 

The evils arising later are due to self-poisoning ; there is an insufficient 
depuration in consequence of the suppression of the cutaneous emunc- 
tory and the increase of autogenous poison. Experiments have demon- 
strated that burned tissues are very poisonous. 

In a great many cases skin burns are accompanied by burns of the 
mucous membranes ; these are due, in general, to the direct inhalation 
of flames, or may be caused by the ingestion of boiling liquids, as is 
the case with English children, who very often burn the mucous mem- 
branes of their throat and larynx by imbibing hot tea from the spout 
of the teapot. The results are the same as those observed on the skin, 
except that the effects are much more serious, for the resulting oedema 
impedes the play of the organs, and, if the patient does not succumb, 
the consequent scars may ultimately cause strictures in certain pas- 
sages, particularly the esophagus. 

In cases of fire, the phenomena are more complex. For we must 
first take note of the great quantity of gas produced. It has been 
calculated that 1 kilogramme of burning wood suddenly yields by a 
silent explosion 200 litres of gas, which, under the influence of heat, 
expands to 10,000 or 20,000 litres. The temperature at this moment 
is very high ; at the focus of the conflagration it is not rare to find 1,000° 
to 2,000° C. 

Death may be due to poisoning by gases produced, and particularly 
by carbonic oxide, which, causing asthenia or paralysis, prevents the 
victims from escaping. At the autopsy the blood is found to be bright 
in colour, and it can be shown by the spectroscope that the hemoglobin 
is no longer reducible by sulphhydrate of ammonia. 

In those who succumb under the influence of heat are found, be- 
sides burns of the skin, intrapulmonary coagula, appearing in the 
form of small casts. When the temperature is very high the thoracic 
cavity is largely open, by a clean cut, as if by a cutting instru- 
ment. The heart is hard, rigid, containing coagulated and dark 
blood. 

With these great burns caused by fire we may parallel those produced 
in explosions of fire damp. The lesions reach the respiratory mucous 
membrane and are explained by the following mechanism: The fire 
damp, mixed with the air which the miner breathes, fills his lungs ; the 
external explosion propagates itself to the interior of the respiratory 
apparatus and produces burns in the trachea and bronchi, ecchymoses, 
and pulmonary hemorrhages. 

In mines where there is no fire damp there may be observed, as 
Eiembault has shown, a sudden deflagration of coal dust, which flies 
in the air and fills the respiratory passages ; in this case also internal 
burns of a very serious nature are produced. 



PHYSICAL AGENTS 45 

Heat Stroke; SunstroTce. — Besides its local action, the heat may- 
give rise to a series of general manifestations which constitute heat 
stroke ; this may be compared to snnstroke. 

Heat stroke is most frequently observed in those workmen who 
labour in overheated places, among glass blowers, foundrymen, firemen, 
and particularly those employed in the firerooms of steamships. In 
the Eed Sea, which lies between abrupt mountains, the heat of the 
climate, added to that of the engine, intensifies the symptoms to such 
a degree that it has been necessary to replace European by negro fire- 
men, who can better resist high temperatures. 

The sun claims numerous victims even in our own country. During 
the summer, cases of sunstroke are often observed among harvestmen, 
especially when they sleep in the sun. But it is soldiers that are most 
frequently affected. To the action of heat is added that of fatigue; 
hence accidents are much more frequent among the infantry than the 
cavalrymen, and occur mostly on the occasion of great manoeuvres or 
reviews. 

We must note also the humidity of the air in order to take into 
account its effects. Dry heat is, as already stated, far more easily 
resisted. Lastly, we must not forget that the most serious accidents 
occur when the heat or the sun acts upon the head. This is a fact of 
observation confirmed by experiment. By circulating hot water 
through a rubber bag Dr. Vallin was not able to produce symptoms 
except when he applied the apparatus to the heads of the dogs under 
experiment. We must also take into account our clothes, which may 
store up heat. After an hour's promenade in Paris, in the month of 
July, on a very sunny day, Tallin found under his hat a temperature 
of 46° C. At the end of a review in the sun the helmets of cavalrymen 
are often hot enough to burn the hand. 

With a view of better analyzing the symptoms of heat stroke, Vallin 
subjected dogs to the- action of the sun. The symptoms manifested 
themselves in three periods. At first the animal struggled and ejected 
saliva abundantly (it is known that the dog does not perspire) ; the 
temperature of the rectum rose from 39.5° (the normal temperature of 
dogs) to 42° or 43° C. Eespiration reached the high rate of 200 per 
minute. In the second period the breathing became slow — it fell to 80 
or 60; the agitation was followed by a complete prostration. The 
third period was characterized by convulsions, which terminated in 
death; at this moment the temperature of the rectum reached 44° 
or 46° C. 

With man the evolution is less clear. We may, with Dr. Lacassagne, 
admit three periods. The first period, the least serious, is announced 
by certain premonitory symptoms — uneasiness, feebleness, heaviness in 



46 INTRODUCTION TO THE STUDY OF MEDICINE 

the limbs. If the sufferer rests, all these symptoms disappear; if he 
continues to walk and expose himself to the heat, the lower extremities 
grow weak; respiration becomes difficult, dyspnoic; the thorax aches; 
the face is flushed; the cutaneous vessels become turgid. This is the 
asphyxial form. 

In other instances, always in the first degree, the heat affects the 
circulation and gives rise to a syncopal form. The onset is abrupt ; in 
the midst of a conversation, for example, the person is suddenly at- 
tacked ; the face is deadly pale. 

As a rule, the first degree is not serious; as soon as the patient is 
put in a cool place the symptoms disappear. 

The essential characteristic of the second degree is the addition of 
nervous phenomena; there are dizziness and delirium; finally, coma 
ensues, and in certain cases death. 

The third degree is that which causes rapid or sudden death, and is 
particularly observed in tropical lands. 

Recovery, even in slight cases, is not always complete. Various 
disorders may persist, notably neuralgia, headache, and sometimes sub- 
delirious ideas. 

The prognosis of sunstroke changes totally with latitudes ; in tem- 
perate countries recovery is the rule; in countries where the tempera- 
ture rises over 40° C. two thirds of the persons affected succumb. 

Several theories have been suggested to explain the mechanism of 
the symptoms. The first idea attributed them to the coagulation 
of the myosin, which is produced at 45° C, but at the autopsy the mus- 
cular tissue is found acid and rigid, and notably the heart is contracted . 
and hard. This view, advocated by Vallin, is being abandoned. In 
fact, it is established that the muscles are able to stand heat much 
better than was believed. Atanasiu, Carvalho, and Richet injected into 
the veins or peritoneum of dogs salt water heated to 60° C. without 
producing any disturbance. This burning liquid is perfectly well borne 
by the tissues and the heart. Therefore, it is more just to ascribe the 
disorders to an action upon the nervous centres, which are, in fact, 
the most delicate parts of the organism, and hence also the first to feel 
the influence of a rise of temperature. This theory, developed by Drs. 
Laveran and Regnard, seems to harmonize more satisfactorily with 
clinical and experimental results. 

Cold 

Cold climates, as above stated, are much more healthful than warm 
climates. Explorers who have been in polar regions state that they 
stood without any suffering temperatures from 40° to 45° C. below zero, 
provided there was no wind. Life may be maintained at even much 



PHYSICAL AGENTS 47 

lower temperatures : at — 60° and — 70° C. However, the facts 
should not be exaggerated. In Russia, for instance, about seven hun- 
dred persons perish yearly through cold. 

All ages are not equally fitted to stand severe cold. The adult 
resists best. The aged, whose nutrition is weakened, need a warm tem- 
perature. Children are very quickly chilled, but their tissues stand 
very well the loss of heat, and they survive depressions of temperature 
to which an adult would have succumbed. M. Edwards exposed to 
cold newborn dogs; the central temperature fell to 14° and even 13° 
C. ; the animals, on being warmed again in a slow and gradual manner, 
recovered. 

Sensibility to cold is increased by all causes which weaken organic 
resistance. Misery, overwork, starvation, and depressing moral 
influences must be mentioned first. This is the reason why cold acts 
so dreadfully upon a routed army. During the retreat from Russia, 
of which Larrey and Desgenettes have left us such striking accounts, 
the greater part of the soldiers died from the cold; the army, which 
comprised 400,000 men at its departure, was reduced to 3,000 when it 
returned to Germany. 

Even in warm countries symptoms may be produced by exposure 
to cold, at least during the night. This is what happened during the 
African wars. In 1870, on the other hand, the accidents were mostly 
due to local freezing. 

Another agency which frequently co-operates with cold is alcohol. 
In cold countries the inhabitants, especially cabmen, are very often 
seen entering wine shops to warm themselves. If they consume hot 
infusions, as tea, they can resist the outer temperature more easily; 
but if they take alcoholic drinks, and particularly brandy, as they do 
in Russia, on going out to the street, they often suffer from serious dis- 
turbances, and sometimes fall dead. 

In order to fully Recognise the action of cold, we must also take into 
account the wind and the humidity. The wind aggravates the cold, 
for it drives away the warm air surrounding the body. The humidity 
increases the loss of heat. Finally, melting snow is borne with diffi- 
culty, for it absorbs a great quantity of heat. 

Furthermore, daily observation establishes the fact that cooling, 
when it is gradual and not abrupt, is more easily endured. An experi- 
ment of Paul Bert evidences this fact. Fish die when they are trans- 
ported, without any transition, from water at 28° C. to water at 
12° C. The converse is also true, demonstrating the danger of rapid 
warming. 

As in the case of heat, we shall successively consider the influence 
of the local and general action of cold. 



48 INTRODUCTION TO THE STUDY OF MEDICINE 

The local action is utilized in therapeutics. When it is desired to 
make a small operation, the diseased part is cooled, either by a mixture 
of ice and salt or by a vaporization of chloride of ethyl or methyl; 
the skin becomes white, bloodless, and insensible. When the cold 
application is stopped, reactionary phenomena are produced; the skin 
becomes red, congested, and the sensibility is exaggerated. The same 
method is applied, as is known, in the treatment of neuralgia. The vaso- 
constrictive action of cold is also utilized for the purpose of arresting 
hemorrhages or soothing inflammatory phenomena. 

Frostbite. — When the action of the cold is more intense or more 
prolonged it produces various manifestations known as frostbite. In 
the clinic three degrees are known. 

In the first degree, there are erythema and rubefaction; sometimes 
the cutaneous irritation is sufficiently marked to produce, as a sequela, 
a durable pigmentation. Some examples of this have been observed 
as the result of the use of chloride of methyl. When the irritation 
is repeated, the skin thickens, remains red, and sometimes cracks. 
Such is the erythema pernio, popularly known as chilblain, and is par- 
ticularly observed among lymphatic persons. 

In the second degree, the skin is ulcerated. In the third, eschars 
are formed, entailing the loss of the affected parts. These destructive 
lesions are particularly frequent in thin and exposed regions : at the 
lobe of the ear, at the tip of the nose, and at the ends of the fingers. 

The different lesions characterizing frostbite are due, for the most 
part, to reactions of great violence ; they are not caused directly by the 
action of cold, but by secondary phenomena produced by this patho- 
genic agent. They may therefore be avoided by moderating the reac- 
tions. It is a well-known fact in northern countries that a person 
suffering from cold should not be brought into a hot room. Circula- 
tion must be restored in the affected parts by mechanical means — by 
hard rubbing, rubbing with snow being the preferable mode. 

During the retreat from Russia a great number of soldiers suc- 
cumbed to terrible symptoms when they were transported into warm 
rooms. The affected parts were tumefied, distended by a considerable 
amount of serum; there was a disengagement of gas; the skin, swollen, 
was sphacelated, and death ensued in a few hours. 

The greater the intensity of cold suffered the more serious are its 
effects. Operating upon the ear of a rabbit, Cohnheim obtained the 
following results : A freezing mixture at — 3° or — 4° C. excites sec- 
ondarily a transient hyperemia; at — ?° or — 8° C. it causes oedema; 
at — 10° or — 12° C, swelling; at —18° or —20° C, gangrene. 

The mechanism of the accidents just indicated is easy to understand. 
Under the influence of cold the circulation grows slow; then, if the 



PHYSICAL AGENTS 49 

temperature of the tissues falls to — 15° C, the blood and the lymph 
coagulate. The red corpuscles become indented, burst, and their con- 
tents are set free. The hemoglobin passes into the urine; the stroma 
forms little foreign bodies, which obstruct the vessels and become the 
starting points of thromboses. When reaction is produced, the blood 
returns in abundance, and, unable to pass through the obstructed ves- 
sels, it transudes through the walls, causing oedema, while the most 
peripheral parts, deprived of the nourishing juice, soon sphacelate. 

If the person succumbs, the same lesions are found as in those who 
have been burned. They depend on the same mechanism — that is, on a 
self-poisoning by the altered and destroyed red blood corpuscles and 
cellular elements. They are expressed also by gastrointestinal ulcera- 
tions, congestion, and sometimes hemorrhages of the abdominal vis- 
cera, lungs, and nervous centres. 

General Effects of Cold. — The general effects of cold are quite com- 
plex; we must discriminate between ailments produced by cold itself 
and those in which cold plays an auxiliary part. 

The first phenomenon consists in a general weakness, a feeling of 
fatigue, and an irresistible tendency to sleep. During the retreat from 
Eussia the soldiers used to pray to be allowed to rest and sleep a few 
minutes ; and yet they could see that those of their comrades who fell 
asleep never woke up again ! 

This state of apathy is sometimes interrupted by cerebral derange- 
ments, delirium, or by epileptiform convulsions. As Brown-Sequard 
has shown, when the body temperature falls to 22° C. there is pro- 
duced, probably by the paralysis of superior centres, a medullary exci- 
tation, which is expressed by an exaggeration of reflexes, just as in 
animals poisoned by strychnine. 

At the start, the organism tries to struggle by means of a more 
active combustion; until 30° C. is reached the exhalation of carbonic 
acid is increased. But when the temperature falls below 26° C, the 
organism abandons itself; nutrition grows slow or is arrested; the 
exhalation of carbonic acid is reduced, or at least its formation dimin- 
ishes, since the blood in the veins becomes red, sugar ceases to be 
consumed, and glycosuria sets in. 

Still, in most cases, death does not result from arrest of general 
nutrition; it is due to arrest of the heart's action. This is a point 
to which Drs. Eichet and Eondeau have called attention; they have 
shown that it is possible to revive beings apparently dead through 
cold if, even half an hour after the cessation of manifestations of life, 
artificial respiration be practised, provided, however, that this is pro- 
longed for a while, often for a very long time. The practical impor- 
tance of this demonstration is readily understood. 



50 INTRODUCTION TO THE STUDY OF MEDICINE 

In cases which we have thus far studied cold did not act solely by 
producing a loss of heat; it caused at the same time an excitation of 
the nervous terminations. The phenomena are, in fact, very complex, 
for it is possible to inject into the veins large quantities of ice water 
without producing any symptoms. This experiment is the reverse of the 
one we have recalled with reference to heat. We may also introduce 
as much as 100 and 160 cubic centimetres of ice water per kilogramme 
without giving rise to any disorder. The internal temperature falls 
2° to 5° C. ; at the end of one or two hours it returns to the normal ; 
then it rises from 1° to 1.5° C. above the initial figure. Thus is pro- 
duced a reactionary hyperthermia, which is, however, transitory. 

Intraperitoneal injections of ice water are equally well borne and 
produce no disorder, not even diarrhoea. On the contrary, in injecting 
the liquid by the central end of the carotid artery, we often see con- 
vulsions, nystagmus, and movements of rotation or manege supervene. 
This is because the icy liquid passes through the carotid and vertebral 
arteries, reaches the nervous centres, and gives rise to the formation 
of softening foci in the brain, the cerebellum, and the peduncles. 

Whatever the mode of introduction, the ice water has never caused 
diarrhoea, pulmonary alterations, or urinary symptoms. These mor- 
bid symptoms are indeed often observed after an attack of cold. In 
this case, however, the cold does not produce simply a reduction of 
heat; it gives rise to extremely violent and sometimes rapidly fatal 
nervous excitations. A guinea pig plunged into water at 4° C, 
care being taken to keep the head in the air, ceases to breathe and 
succumbs within a few minutes. This result is important from a 
medico-legal standpoint. Some individuals have survived after 
having remained quite a long time under water, while others, 
brought out sooner to the air, could not be restored to life. The differ- 
ence depends largely upon the temperature; if the liquid is not too 
cold, the subject breathes, water is introduced into his lungs, and he 
is asphyxiated. If, on the contrary, the water is intensely cold, a car- 
diac and respiratory syncope takes place and the water does not pene- 
trate the bronchi. In the first instance the drowned person is blue; 
in the second he is white (white asphyxia of certain authors), and, if 
artificial respiration be practised, he survives even if he had remained 
in the water for ten or fifteen minutes. 

In order to put a little system into our study, we shall divide the 
morbid occurrences occasioned by cold into five groups : 

Cold may produce painful phenomena. In many cases, particularly 
with arthritic subjects, a simple draught of air causes a facial neural- 
gia, often accompanied by an outbreak of herpes. In other instances 
motor disorders are produced — for example, a facial, perhaps even a 



PHYSICAL AGENTS 51 

radial paralysis, although in the latter case, as already stated, it is 
generally due to a process of compression. Finally, with certain per- 
sons, extended paralysis has been observed, assuming usually the form 
of paraplegia. 

A second group of phenomena consists of reflex disorders affecting 
mostly the vasomotor system. It is admitted that cutaneous cooling, 
involving a contraction of the superficial vessels, produces as a com- 
pensation a congestion of the deeper organs. As an example, reference 
is made to the results discovered at the autopsy of alcoholics dead 
under the influence of cold; a very marked congestion is found, and 
sometimes hemorrhages in the brain and lungs. Even in such cases 
the phenomena are complex, and congestive manifestations may be 
regarded as secondary. In fact, it is a matter of frequent observation 
that cooling of the skin excites vaso-constriction in the deeper tis- 
sues. Fredericq has given experimental proof of this. By submitting 
the cranial skin of a dog to cold, a vaso-constriction of the meningeal 
vessels is produced. The phenomenon is too rapid to be attributed 
possibly to a reduction of heat; it is a case of reflex action. On the 
ground of this result it may be questioned whether pulmonary conges- 
tion, which is attributed to cold, is not a secondary manifestation, 
preceded by an initial vaso-constriction. We shall return to this ques- 
tion when treating of infections and nervous reactions. 

In the third group are ranged the hypercrinic phenomena. Water- 
ing of the eyes, nasal catarrh, polyuria, and diarrhoea represent the 
best-known manifestations. 

The fourth group consists of those cases in which the cold serves as 
an auxiliary cause to an infectious agent ; it diminishes our resistance, 
and thus favours the development of bacteria, which live on our bodies 
as simple parasites. Hence, exposure to cold may be followed by angina, 
laryngitis, or pneumonia. In other cases cold provokes a relapse ; such 
is the case with a person who, recovering from erysipelas, leaves his 
room too soon and is again attacked by the disease. Finally, cold may 
cause the development of complications in the course of a pre-existing 
disease by provoking secondary infections in the respiratory passages. 

The last group, the least well known, comprises those very curious 
cases in which the cold gives rise to an attack of gout, or to the repro- 
duction of an ascites in cirrhotic subjects. Finally, though in a man- 
ner as yet unexplained, cold may cause also paroxysmal hemoglobinuria. 
With certain subjects the urine contains hemoglobin as soon as there 
is a cutaneous cooling, even over a limited region. The phenomenon 
may thus be provoked at will. 

It is a remarkable fact that cold does not seem to act any longer 
after a certain limit. Pietet demonstrated that one may descend into 



52 INTRODUCTION TO THE STUDY OF MEDICINE 

a well showing a temperature of — 100° or — 110° C, the head remain- 
ing out. After staying there ten minutes the appetite is strongly 
aroused and the previous dyspepsia is notably decreased. 

ChoisVt and Cordes utilized this result in therapeutics, and Letulle 
and Eibard conceived the ingenious idea of treating the anorexia of 
consumptives by the aplication upon the abdomen of carbonic snow at 
about — 80° C. Let us remember also that Dr. d'Arsonval has shown 
that the finger can be dipped with impunity in liquid air, or some of it 
poured upon a mucous membrane. It is more than probable that still 
lower temperatures would be even better supported. The human body 
would become wholly diathermanous, and the radiations would traverse 
it without making any kind of impression upon it. 

Light 

Light has a very marked influence on all living beings. It may 
sometimes become destructive; microbes perish under it's influence. 
Most frequently its action appears by the very notable modifications 
of nutrition in plants as well as in animals. 

In the higher animals it stimulates the nerve ends, thus enhancing 
the nutritive activity. From this results an increase of resistance to 
pathogenic causes, a more energetic working of the organs, a notable 
improvement in ideas and feelings. Joy and cheerfulness are proverbial 
in sunny countries. 

Certain experiments were made confirming these data. Let us rep- 
resent by 100 the carbonic acid exhaled through the skin and lungs 
by a person shut in darkness. If this man is brought to the light, 
keeping his eyes shaded, the quantity of carbonic acid exhaled rises 
to 112. If the light is brought to bear upon the eyes, carbonic acid 
rises to 114. If the light acts at the same time on the body and 
visual apparatus, the acid reaches 136— that is, an increase exceeding 
the sum of the two preceding partial results. This increase of carbonic 
acid obviously indicates a nutritive overactivity; it coincides with an 
elevation of the bodily temperature. The result is particularly evident 
in children; their temperature rises from 0.1° to 0.5° C. when they are 
brought from darkness into daylight. 

Light may, however, produce certain disturbances. The solar rays, 
arriving directly or after being reflected upon surrounding objects, cause 
an erythema, sometimes accompanied by a slight elevation of the epi- 
dermis by serous liquid. Electric light gives rise to analogous effects. 

In the south of France and in Spain a disease is observed— i. e., 
pellagra, which is characterized by a chronic erythema occupying the 
exposed parts. There has been a good deal of discussion concerning the 
pathogeny of this affection; it seems to be due to the co-operative action 



PHYSICAL AGENTS 53 

of different causes. In fact, it is observed in persons who consume 
spoiled maize. The alimentary poisoning engenders various nervous 
ailments and serious manifestations of a general character ; at the same 
time it diminishes the resistance of the skin to the action of the solar 
rays. The eruption does not appear over parts protected by the clothes. 

The notion that the harmful effects of the sun may be avoided by 
protecting the skin by means of blue or black glasses is a familiar one. 
Freckles act in the same way ; the solar erythema does not appear where 
freckles are present. 

The mucous membranes are even more sensitive to the action of 
light than the skin. The blepharitis and ophthalmia which are ob- 
served in hot countries and in those lands where the sun strikes the 
eye after being reflected from snow are well-known proofs of the fact. 

The pathogenic action is due to the chemical rays of the spectrum — 
namely, to the violet and ultraviolet rays. Dr. Bouchard has demon- 
strated this fact by causing a ray of sunlight decomposed by a prism to 
fall upon the skin of his arm; the erythema appeared only in those 
parts that were exposed to the chemical rays. 

The light may also give rise to reflex phenomena. On passing 
from darkness to daylight one is seized with sneezing. By gazing at a 
luminous object for a long while an artificial slumber may be induced, 
known by the name braidism, in honour of the author who discovered 
this phenomenon. The subject under experiment is found sufficiently 
asleep to make it possible, without awakening him, to perform painful 
operations upon him. By this procedure, even animals, particularly 
pheasants, may be made to fall asleep. 

If the light shine brightly, it may produce more complex phenomena 
in predisposed subjects. When a magnesium lamp is lighted, catalepsy 
is caused; the person remains motionless in the very situation which 
he occupied, no matter how fantastic. If the light is suddenly put 
out, catalepsy gives way to lethargy. 

The action of light may be compared to that exerted by the Eontgen 
rays. Their prolonged application has caused skin lesions, simply 
erythematous in most cases, but sometimes liable to end in the forma- 
tion of small eschars. At the same time modifications in the general 
nutrition are induced, which are perhaps the result of the excitation 
of nerve terminations in the skin. This is a process comparable with 
that known in therapeutics as revulsion, and explains the effects ob- 
tained by the use of cathodic rays in the treatment of certain diseases. 

Sound 

The vibrations of sound sometimes produce intense mechanical 
lesions, even a perforation of the tympanum. More often they act 



54 INTRODUCTION TO THE STUDY OF MEDICINE 

by reflex action and stimulate activity in the nerve centres. Nothing 
is more restful than the absence of noise in the country or in the 
mountains, at least for certain persons, for, in others, silence may 
engender sadness and melancholy. 

Noises, if intense, may produce disturbances in the predisposed. 
At the strike of a gong, hysterical persons fall into catalepsy. 

Finally, it has been thought that harmonious sounds might serve 
as therapeutic agents, and that music might be used in the treatment 
of certain diseases. It is well established that music exerts a consid- 
erable influence over the nervous system. Its action deserves to be 
studied anew. 

Electricity 

To appreciate the action of an electric current two factors must be 
considered : the energy of the current and the resistance of the bodies it 
traverses. 

The unit of electric resistance is the ohm ; it is the resistance of a 
cylindrical column of mercury, one metre long and one square milli- 
metre in cross section, at a temperature of 0° C. The resistance of 
the human body is, on an average, 1,000 ohms ; this figure is obviously 
subject to great variations. Moreover, it must be noted that the re- 
sistance is not always the same during the passage of the current, and 
that it diminishes as the electric energy is increased. 

Again, the resistance varies according as the current passes by this 
or that part of the body. Stone finds that the resistance, which 
amounts to 939 ohms when the current passes from one foot to the 
other, falls to 905 when it passes from the hand to the foot. 

The second factor to be taken into account is the energy. In order 
to make it clear we may represent the form of the current graphically. 

Let us suppose a continuous current 
passing in a nonelectrified body — viz., a 
body whose electric potential is equal 
_ to 0. We may distinguish in the elec- 
A E trie wave ( Fig. 1 ) three periods : a 

Fig. l.-Electric wave continuous ^ of increa a stationary period, 

current. O O, line of zero poten- x J L 

tiai ; a B, period of increase ; and a period of decrease. The first and 
B (7, stationary period ; CD, pe- third periods, which correspond to the 

riod of decrease : BE measure beginning and the end of the passage f 
of electric energy, difference of ° , . 

potential. the wave, constitute variable states; 

the stationary period is called the per- 
manent state. Measuring by a perpendicular the distance which 
separates the permanent state from the line whence the current starts,, 
we shall have the energy of the current; this is the difference of the 



PHYSICAL AGENTS 



55 



O A d c o 

Fig. 2. — Electric impulse. 
O 0, line of zero poten- 
tial ; A B, the period of 
increase ; B C, period of 
decrease ; no stationary 
period ; B Z>, difference 
of potential. 



potential existing on the body considered before and during the passage 
of the wave, and if the useful effect is considered, it is called electro- 
motive force. The unit employed to measure electro-motive force is 
the volt; this is nearly the electro-motive force of a Daniell cell, 
which is taken as a standard on account of its great constancy. The 
ratio between the electro-motive force of a current and the resistance 

of a body is called the intensity of the current. The formula I = ^ 

allows us to determine easily this new unit, which is known as the 
ampere. The resistance of the human body being equal to 1,000 ohms, 
we must always, in our calculations, divide the number of volts by 
1,000 to find the intensity. Consequently, it has 
been found simple in electro-physiology to meas- 
ure by milliamperes. 

Let us return to the form of the current. 
Suppose the permanent state is suppressed; 
a single impulse (Fig. 2) will be obtained; this 
is what is realized in the electric spark, the dis- 
charge of a Leyden jar, and the lightning flash. 
Again let us suppose that in a continuous 
current a series of breaks is made; then an in- 
terrupted current will be the result. But while 

continuous or interrupted currents are used they do not cause electri- 
cal effects only. Chemical effects are at the same time produced, owing 
to the electrolytic phenomena to which the current gives rise in the 
body, as in saline solutions. This chemical action may be suppressed 
by the use of alternate currents, the most important of which are the 

sinusoidal currents (Fig. 3). 
Each wave moves in a direction 
opposite to the preceding one; 
the successive figures are added, 
and, as they are in opposite 
directions, they neutralize each 
other. These currents therefore 
exercise a purely electrical ac- 
tion. The number of waves pro- 
duced in one second is called fre- 
quency ; double waves — i. e., two 
waves of opposite directions — are 
called periods. It is to be noted 
that in currents of this kind the body at each period undergoes a 
diminution of potential equal to twice the energy of the current. If, 
for example, the current is one of 500 volts, the two successive waves 
5 




Fig. 3. — An alternating sinusoidal current. 
O O, line of zero potential ; AD B, wave 
of positive electricity ; B F C, a similar 
but negative wave ; A B and B C, length 
of waves ; A C, length of a period ; D E, 
F 6r, difference of potential with reference 
to the line O 0\ B F, measure of "deni- 
vellation " of potential at each period. 



56 INTRODUCTION TO THE STUDY OF MEDICINE 

being of opposite directions, there would be between them a difference 
of potential of 1,000 volts. 

We shall have finished these few preliminary remarks when we have 
added that the action of currents on the living organisms depends upon 
the form of the waves. When the waves are similar the effects are 
identical, whatever may be the electrical source. 

If the organism is subjected to the action of a single wave, such as 
is realized in a lightning flash, sudden death may be the result, which 
is due to anatomical lesions and hemorrhages produced in the nerve 
centres, particularly in the medulla. 

If the victim does not succumb, paralyses may persist, some of 
which are due to a material lesion, while others belong to the category 
of hysterical phenomena, called by Charcot Tcerauno paralyses (herau- 
nos, lightning). 

Continuous currents act upon the organism only when the potential 
is being modified; that is, during the variable periods — the closing or 
the break of the current. So long as the permanent state lasts no 
phenomena occur, excepting, of course, the disturbances due to elec- 
trolysis. 

If an animal is subjected to the action of a continuous current of 
sufficiently high potential — for example, 400 volts — at the closing and 
opening of the current a muscular contraction is produced. If the 
shocks be repeated a great number of times the animal is killed. But, 
as d'Arsonval has shown, in such a case death is due to the large 
amount of heat generated by muscular work; for, if this experiment 
be repeated upon an animal plunged into a cold bath survival is the 
rule. 

Very powerful continuous currents, amounting, for instance, to 
several thousands of volts, may produce a fatal shock. In the indus- 
tries, continuous currents furnished by dynamos are much more dan- 
gerous than currents supplied by batteries; for the break currents 
give rise to phenomena of self-induction and to the production of extra 
currents which, if the voltage is high, produce sideration. A current 
short of 300 volts produces but one shock; between 300 and 1,000 
volts it causes a very painful sensation; at 3,000 volts it may, though 
not always, entail death. 

From a physiological standpoint the most interesting currents 
are the alternating currents, the effects of which were thoroughly stud- 
ied by Tesla and d'Arsonval. 

Let us suppose a sinusoidal alternating current having no chemical 
action; if the potential is low, and if the frequency is also low, the 
current produces no notable effect upon the human body; it modifies 
only the nutrition, as may be shown by analyzing the urine. 



PHYSICAL AGENTS 57 

Ac a moderate potential and a moderate frequency the current 
produces a muscular contraction which is not painful. 

If the potential is raised, and if the frequency is from 100 to 200 
per second, sinusoidal currents give rise to serious and even fatal 
accidents. These currents have been most extensively utilized in indus- 
tries and are also used in America for electrocution. 

Let us now assume that the potential and the frequency are in- 
creased. The action will be more and more marked, and then, for an 
instant, the effects on the organism will no longer vary ; beginning from 
2,500 to 5,000 excitations per second, the manifestations diminish. 
When the frequency reaches several hundred millions or several billions, 
whatever be the voltage, the currents become harmless. 

The following experiment, repeated a great many times in Professor 
d'ArsonvaPs laboratory, well illustrates this point. A steam engine 
furnished a current which was used for electric illumination and which 
accidentally caused the death of a man. This current, when trans- 
formed to an alternating sinusoidal current at high frequency, can 
harmlessly traverse the human body. Two men desire to be experi- 
mented upon; each one puts himself in contact with one of the poles. 
Then the two men are joined by a metallic conductor bearing six in- 
candescent lamps; the six lamps are lighted, while the men do not 
experience the slightest sensation. And yet, if the frequency was 
diminished, the two persons would soon be killed. 

To explain the innocuous character of high-frequency currents, 
Professor d'Arsonval has advanced two hypotheses. We may admit 
that the current has no power of penetration and that it simply glides 
over the surface of the body. On the other hand, we may suppose that 
the nervous system ceases to be influenced when electric vibrations 
become too frequent. In support of this conception the cases of light 
and of sound are recalled. The auditory nerve is impressed only when 
the waves have more than 30 and less than 30,000 vibrations per second. 
The retina perceives but those rays whose vibrations are comprised 
between 497,000,000,000 and 728,000,000,000 per second. Below or 
above these figures there is no stimulation. Why, then, should we not 
admit for electricity what is demonstrated for sound and light ? 

Currents of moderate frequency used in the industries have caused 
a number of accidents, many of which have been fatal. 

But, in view of the extent which electrical industries have reached, 
we must recognise that the number of fatal cases is by no means very 
considerable. Biraud, in his excellent thesis, was not able to collect 
more than 10 such cases in France and 20 in England. In America, 
where the use of electricity is so extensive, he found only 200 cases. 

In factories a number of precautions are observed which, if well 



58 INTRODUCTION TO THE STUDY OF MEDICINE 

followed, would be entirely efficacious. Workmen must protect their 
hands by the use of rubber gloves. It is to be remembered, however, 
that the rubber, in getting old, may crack and let the electricity pass. 
Another precaution consists in not wearing shoes with nails, and in 
using rubber soles. This measure is excellent, for the most serious 
accidents have been those which are caused by currents passing from 
the hands to the earth. Finally, the tools are provided with insulating 
handles. 

If, through neglect of these precautions, an accident happens, the 
effects vary according to the extent of the contact, the condition of 
the parts affected, and the position of the body with respect to the 
current. 

It is quite evident, in the first place, that the more extended the 
contact, and the better conductors the parts through which the cur- 
rent enters or leaves, the more serious will be the injury. The humid- 
ity of the hands, for instance, favours considerably the penetration. 
But it is especially the position of the body with respect to the cur- 
rent that modifies the results. 

Three events are possible. The two hands touch two points of a 
conducting wire, thus completing the circuit. The resistance of the 
body being higher than that of the wire, the effects will not in general 
be serious. 

In other cases, the entire current passes through the body — for 
example, when a workman takes the two ends of a broken wire to 
mend them. If the current does not reach the ground, the effects are 
often almost harmless. 

Finally, when the current reaches the ground, the phenomena of 
sideration supervene; currents of 2,000 volts may bring about death, 
while in the preceding cases currents of 3,000 volts caused some 
shaking. 

The effects produced by currents may be divided into two groups. 
Some of them are local manifestations — burns which are more or less 
intense, according to the degree of resistance. They are therefore 
observed in relatively harmless cases, when, for example, very dry 
hands resist penetration. If, on the contrary, the hands are moist, 
they are good conductors and the phenomena of sideration are pro- 
duced. These are very simple; the person falls as if struck by light- 
ning and his respiration is arrested. Yet the accidents are not irre- 
mediable; it is only a case of apparent death, a variety of nervous 
shock, and if artificial respiration is practised for a sufficient length 
of time he is restored to life. But sometimes there occur irremediable 
hemorrhages in the nervous centres. These lesions, which were the 
rule in the case of fulguration, are rarer in sideration. This is one 



PHYSICAL AGENTS 59 

difference between the two states. There is another difference. The 
kerauno paralyses of Charcot are observed only after figuration; 
they do not appear after sideration. 

Electrocution. — The idea of utilizing electricity in capital execu- 
tions seems to belong to a French senator, but the experiments were 
made in America. Brown and Kenelly were asked to determine the 
fatal effects of the electric fluid on animals. They used currents of 
200 to 280 alternations per second, and succeeded in killing a dog 
with 200 volts ; 700 volts killed a horse. 

The first experiment on a human being took place on August 6, 
1890, in the prison at Auburn, N". Y. The condemned person 
was seated on a wooden chair and tied fast. A casque was put on the 
head and a wet sponge on the sacrum; the preparations took three 
minutes. Then a current of 2,376 volts was passed for seventeen 
seconds; the person seemed to be dead, but a few minutes afterward 
the pulse revived, and at the end of thirty seconds a slow movement 
of the thorax seemed to be noticeable. The current was again applied 
for seventy seconds, and this time he succumbed. 

The following year, on the same day, there was occasion to make 
four capital executions. With the first condemned one, a current of 
1,548 volts, passing from the head to the calf for 37 seconds, did not 
prove fatal, and a second contact of 36 seconds became necessary. 
For the three others, currents of 1,845 volts were used; for each one 
three successive contacts of from ten to eighteen seconds were required. 

These results appeared excellent, and in 1892 it was considered 
proper to invite to the execution a number of persons, especially jour- 
nalists. After a lecture delivered by the physician in charge of the 
operation, the condemned man was brought in. They dipped his 
hands in acidulated water, and, as a precaution, in case the new system 
should not succeed, the casque was applied to his head and the wet 
sponge to his calf. The current, of 1,600 volts, passed through the 
hands for fifty seconds. By this time the water had evaporated and 
the hands were carbonized. Yet the heart was beating; then the 
mouth opened and saliva was thrown out, certain movements were 
produced, and several spectators heard a groaning. Then the cur- 
rent was applied from the head to the calf for thirty seconds, and 
he succumbed. 

At a subsequent execution it was decided to verify the value of 
artificial respiration, advocated by Professor d'Arsonval as a treat- 
ment of sideration. The experiment met with a marvellous success 
and saved the life of the condemned. This fact is obviously very 
important from a practical standpoint, and is perhaps the best result 
furnished thus far by electrocution. 



60 INTRODUCTION TO THE STUDY OF MEDICINE 

Practical Applications of Electricity. — The practical medical appli- 
cations of electricity are very numerous. It may be used for diag- 
nostic as well as for therapeutic purposes. The study of electro- 
muscular contractility plays a very great part in nervous semeiology. 
Therapeutists use the electric fluid in all its forms, static electricity, 
continuous and broken currents, and currents at high frequency. It is 
particularly in nervous affections that electricity is of service; it is of 
real utility against paralyses and muscular atrophies; it is equally 
valuable in combatting tics, cramps, and neuralgia. It is used in cases 
of atony of organs supplied with unstriated muscular fibres. Many 
successes have been obtained even by the use of electrical baths in 
cases of intestinal occlusion. 

Finally, whether by static electricity or by currents at high fre- 
quency, success in modifying nutrition or calming general disorders, 
such as those which characterize neurasthenia, has been obtained. 

Electricity may also be used for producing electrolysis. When an 
electric current is passed through saline solutions it causes decompo- 
sition; the acids are attracted toward the positive pole and the bases 
toward the negative pole. The same phenomena occur in the organ- 
ism, and have been turned to use in therapeutics. Electrolysis is em- 
ployed to destroy certain pathological tissues. Although it has been 
abandoned in the treatment of aneurism, it is resorted to in the treat- 
ment of erectile tumours, uterine fibromata, and strictures of the 
urethra. It is also employed for destroying the hair. 

A last application of electricity is the galvano-cautery ; but in this 
case it is not the electric fluid itself that is concerned, but the heat 
which it develops. 



CHAPTER IV; 
CHEMICAL AGENTS 

Caustics — The toxines — Exogenous poisons: alimentary poisons, air poisons, poison- 
ing due to occupation— Criminal, suicidal, and accidental poisoning — Venoms 
— Mode of penetration of poisons — Transformation, elimination, and accumu- 
lation of poisons — The toxic equivalents: their variations — Habit — Anatomical 
lesions of toxic origin. 

In studying the physical agents we considered the contingent prop- 
erties of bodies, those that are independent of their constitution. We 
have viewed the world of energy. With the chemical agents we enter 
the world of matter. We are now about to study those properties 
which depend upon the molecular structure of bodies. 

Chemical agents are divided into two groups : caustics and toxines. 

Caustics 

Caustics are bodies which, by virtue of their chemical affinities, are 
capable of altering and destroying the living part with which they 
come in contact. 

The action of •caustics is known as mortification ; the result is 
called eschar. Mortification is the more energetic the greater the 
chemical affinity of the caustic for albuminoid substances. 

The organism presents various means of protection against the 
action of caustics. The skin is covered with a coating of grease, 
which shields the subjacent stratified epithelium; this resists fairly 
well. If it be reached, alkaline albuminoid secretions are produced 
which neutralize certain substances and form insoluble combinations 
with others. 

Caustics were formerly divided into mild and escharotic or strong 
caustics. To-day they are divided, according to Mialhe, into coagu- 
lating and liquefying caustics. 

Coagulating caustics are represented by metallic salts, acids, and 
some essences. 

Metallic salts, among which silver nitrate, acid nitrate of mer- 
cury, and zinc chloride deserve especial mention, give rise to two types 

61 



62 INTRODUCTION TO THE STUDY OF MEDICINE 

of lesions. Applied to superficial parts, they cause instantaneous 
death of the cells — that is, mortification; they destroy them without 
modification of their normal histological characters. In the deeper 
tissues they produce fatty degeneration of the anatomical elements. 

Acids, of which sulphuric, hydrochloric, nitric, and chromic are 
the most important, often produce very extensive eschars. Although 
their action is diminished by the water they absorb from the tissues and 
by their union with the alkaline fluids, the lesions caused by them are 
generally profound. The aspect varies according to the substance. 
The eschar produced by nitric acid is yellow, owing to the formation 
of xantho-proteic acid. Sulphuric acid produces black eschars, the 
colour being due to an alteration of the colouring matter of the blood 
and to the liberation of carbon contained in the cells. 

Lastly, essences, notably those of cinnamon, bergamot, and meadow 
sweet, possess, according to Dr. Pilliet, the power of causing on the 
surface of mucous membranes lesions similar to those produced by 
sulphuric acid. 

Liquefying caustics comprise the bases potash, soda, and am- 
monia, and an acid — arsenious acid. The bases act by dehydrating the 
tissues and forming soluble soaps by union with fatty substances, also 
by decomposing nitrogenous substances. The eschars are soft, and, on 
separating, leave the blood vessels exposed, frequently causing grave 
hemorrhages. 

The cicatrices produced by various caustics are often severe, and 
may be followed by contractions interfering with motion. Functional 
troubles are particularly frequent when mucous membranes are in- 
volved. For example, strictures in the esophagus result, necessitating 
the establishment of a gastric fistula. 

TOXIKES 

Many definitions of toxic substances have been given. Aside from 
those found in the codes, and which have no scientific value, we 
believe that a much broader meaning should be assigned to this term 
than is usually done. Therefore, we propose the following formula : 

Toxines are those substances which, when introduced into or 
formed within the organism, are capable of disturbing or abolishing 
the life of anatomical elements by either directly or indirectly modi- 
fying the liquid medium containing them. 

We include in this definition the very important group of toxic 
substances formed within the organism — the endogenous poisons — 
among which those concerned in auto-intoxication have been best 
studied. We repeat, that poisons act by disturbing the medium in 
which the anatomical elements live. This is a characteristic distin- 



CHEMICAL AGENTS 63 

guisliing the toxines from all other agents heretofore studied — in fact, 
all the others altered the parts with which they came in contact. 
Toxines, on the contrary, do not act until they have been absorbed, 
have penetrated into the blood and interstitial fluids, and have modi- 
fied their chemical composition. 

Our definition naturally leads to the division of the toxines into 
two groups : exogenous, altogether formed before their penetration 
into our organism; endogenous, which are generated within our own 
bodies. 

Endogenous poisons are subdivided into heterogenous and autoge- 
nous. The former are produced by parasites or microbes accidentally 
or normally lodging in our bodies ; the latter result from the very life 
of our cells. It is a general law that all living cells constantly pro- 
duce substances which, if not eliminated on the one hand while formed 
on the other, derange and arrest the manifestations of life. 

The following table will give an idqa of this division: 



Poison. 



Exogenous. 



j Habitual. 
( Accidental. 

( Heterogenous t Parasites. 

Endogenous 1 < Infectious agents. 

( Autogenous, by cellular life. 

Aside from the endogenous poisons, the history of which will be 
presented when treating of parasites, microbes, and nutritive disturb- 
ances, we shall consider exclusively the exogenous substances. We 
shall review in succession alimentary poisons, air poisons, poisoning 
due to occupation, accidental intoxications — whether criminal or vol- 
untary — and conclude with the history of venoms. 

Alimentary Poisons. — Among the common exogenous poisons are 
to be noted, first, the alimentary poisons, and chief of these the potash 
salts. These salts are useful, indispensable. Dogs fed on meat freed 
from potash salts succumb at the end of ten days — that is to say, much 
sooner than under the influence of absolute starvation. If great quan- 
tities are ingested, the excess is readily eliminated through the urine. 
But if the kidneys are altered, potassaemia results; and some authors 
hold that an accumulation of potash salts is responsible for the phe- 
nomena of uraemia. 

Side by side with the potash salts are often placed the albuminoid 
substances contained in the tissues. It is certain that their intra- 
venous injection speedily causes death. As a matter of fact, however, 
these substances are transformed into peptones in the digestive tract. 
The peptones, being dehydrated in their passage through the intes- 
tinal membranes, form new albumins adapted for the nourishment 



64 INTRODUCTION TO THE STUDY OF MEDICINE 

of the cells. It may possibly happen that, in the case of certain 
lesions of the intestinal membranes, peptones penetrate as such into 
the organism; they are then found in the urine. There has been a 
great deal of discussion in reference to the toxicity of peptones. It 
would seem that, if not peptones, at least albumoses produce noxious 
effects; at all events, when injected into the veins, they can render the 
blood noncoagulable for several hours ; at least, that is what occurs in 
the dog. 

A last cause of habitual intoxication is represented by the putre- 
faction which occurs in the intestinal contents under the influence of 
microbes. We shall again refer to this when studying the bacterial 
agents. 

Alcoholism. — Toxic substances are found in beverages even more 
than in aliments. Water contains mineral salts, and, most important 
of all, the products of putrefaction of organic matter, which render 
it injurious. 

At the present day plain water is seldom drunk ; alcoholic beverages 
are largely consumed which, without exception, are toxic, and in cer- 
tain doses may speedily cause death. One litre of rum is estimated 
to be a fatal dose for an adult. In children, serious accidents occur 
with far smaller doses. Taylor reports the case of a child of seven 
years who died from the effects produced by drinking 100 grammes of 
brand}^. 

We most frequently have to deal with chronic alcoholism. It is 
not necessary to state that this form of intoxication is steadily on the 
increase in the majority of countries. In 1830 France annually con- 
sumed a quantity of beverages corresponding to 1 litre of absolute 
alcohol per capita; in 1885 the consumption had risen to 3 litres, and 
in 1891 to 4 litres per capita. This figure is still below the actual 
consumption. This is established by official statistics, which give for 
each year and for all France 1,545,045 taxed hectolitres. The amount 
of alcohol passing fraudulently is estimated at 500,000 hectolitres. 
The annual consumption for each inhabitant may then be estimated 
at 5 litres, which correspond to 13 litres of brandy. Moreover, if we 
reflect that there are many who consume no alcohol and that children 
drink hardly any, we must acknowledge that the figures are very high. 

Statistics further demonstrate the existence of a striking parallel- 
ism between the advance of alcoholism and the increase of insanity, 
suicides, and crime. We have said that alcoholism is on the increase 
in almost every country. In Denmark, the consumption of alcohol is 8 
litres, and in Belgium 12 litres per capita. In some countries, owing 
to certain measures adopted, the advance of this evil is being checked. 
In the United States the consumption has fallen to 3 litres, and in 



CHEMICAL AGENTS 65 

Norway, where alcohol once made fearful ravages, it does not exceed 
2 litres per capita. 

7^he universally used expression " alcoholism " is incorrect in that 
it takes the part for the whole ; for in the so-called alcoholic beverages 
ethylic alcohol is certainly the least toxic ingredient. According to a 
law which offers very few exceptions, the toxicity of alcohols increases 
with their atomic weight. Alcohols of high atomicity — propylic, bu- 
tylic, amylic, cenanthylic — which are met with in most beverages, 
and particularly in brandy, are far more noxious than the alcohol 
of wine. 

Besides alcohols, we must mention aldehydes, and, among these, 
pyronic aldehyde or furfurol, all of which are convulsive poisons, and 
are found in vermouth and bitters. There are also ethers, acetone, vari- 
ous volatile bases, hydrocyanic acid, and, last but not least, essential 
oils. Absinthe contains nine different essences, all toxic substances. 

We must make special mention of a product too often considered 
as inoffensive — namely, aqua melissae. Women particularly make use 
and abuse of this preparation, which often gives rise to very grave 
disturbances, notably to paralysis, the nature of which is not always 
easily determined. 

We may state in conclusion that alcoholism is a complex intoxica- 
tion, hence the variability and multiplicity of the disturbances. 

Accidental Alimentary Poisons. — In addition to the toxines 
which we ingest in consequence of our social habits, others exist which 
can be regarded as accidental. At the head of the list stands lead. 
Nearly all beverages, water not excepted, contain more or less consid- 
erable quantities of this metal. In cities the water pipes are of lead, 
and water dissolves traces of it. In this event danger is not great, 
as the lime salts contained in the water are deposited inside the pipes 
in such a manner as to form a sort of protective coating. 

Lead is found especially in cistern water, which is pure and aerated, 
and in water containing organic substances in a state of decomposi- 
tion. Although opposed to each other, these two conditions are most 
favourable for the solution of the metal. 

In other cases lead comes from reservoirs painted with vermilion, 
from earthenware varnished with substances containing lead, and, in 
carbonic waters, from metallic vessels. According to Dr. Moissan, 
Seltzer water may contain as much as 0.9 milligramme of lead to the 
litre. 

Alcoholic beverages especially are oftenest contaminated with lead. 
The different pieces of the retorts and presses may leave traces. Un- 
scrupulous manufacturers add litharge to diminish the acidity of wine 
and cider, and acetate of lead to clarify beverages. We must also take 



6Q INTRODUCTION TO THE STUDY OF MEDICINE 

into account the grains of shot that may be left at the bottom of 
bottles after cleansing. 

Aliments are no less contaminated. Take, for example, bread. 
The millstones present small holes which are filled with lead; the 
tubes which conduct the flour to the bolter contain some lead; in the 
bakery refuse wood painted with white lead is sometimes used for 
heating the ovens, which wood gives off small amounts of this metal 
under the influence of the heat. Among other aliments, butter col- 
oured with chromate of lead may be mentioned, and also preserved 
game killed by leaden bullets. Preserves are worthy of particular 
attention. The pewter which is used to solder the boxes contains a 
considerable amount of lead, which is readily dissolved in preserves 
containing oil; in peas, only 2 milligrammes of lead are found to the 
kilogramme; in sardines, 40 to 50 milligrammes; in preserved beef, 
particularly in that intended for use at sea, Schutzenberger and 
Boutmy detected as much as 1.48 gramme per kilogramme. Most of 
the disturbances described as dry colic of hot countries have been 
shown by Amedee Lefevre to be cases of lead poisoning. 

Among other sources of saturnine intoxication we must note pot- 
tery, oilcloths, tinned utensils, the pewter foil surrounding chocolate 
and tea, the grinding machines of the butcher, the oilcloths painted 
with chromate of lead and used for packing ham and cheese, and 
nursing bottles with lead nipples. 

This enumeration sufficiently establishes .the fact that people ingest 
daily a certain amount of lead; consequently, traces of it are often 
found in the urine. Putnam was able to find some lead in 17 per cent 
of the healthy subjects he examined. In the sick the proportion is as 
high as 50 per cent. 

Although the continual absorption of lead at times provokes gas- 
trointestinal disturbances, indigestion, and colic, it most often causes 
chronic manifestations. Arteriosclerosis and interstitial nephritis, so 
frequently observed after a certain age, are very often the results of a 
slow and progressive intoxication by this metal. 

Copper is perhaps as widely diffused as lead, but it is less danger- 
ous. It is found in bread, and especially in wine, since Bordeaux oou- 
illie has been employed instead of mildew. Wine, cider, and beer, even 
without the aid of heat, rapidly attack copper. Condiments prepared 
with vinegar and pickles always contain some. Some is also met with 
in vegetables, which, in fact, possess the property of taking up the 
metal contained in the soil; and notable quantities of it are found 
in the hulls of various grains. 

It is easy to understand that copper might invade the organism of 
herbivorous animals from the vegetables eaten. That is why we find 



CHEMICAL AGENTS 67 

some in the meat we consume. Dr. Gautier thinks that one can toler- 
ate 18 to 20 milligrammes per kilo, but these quantities are often ex- 
ceeded. As much as 200 or 210 milligrammes of copper salts may 
exist in one kilogramme of preserved substances. 

It can be said, then, that we ingest some copper and lead every day. 
Dr. Gautier estimates the minimum at 1 to 7 milligrammes and the 
maximum at 20 to 30 milligrammes. These salts, however, are of 
little toxicity. Taken in large doses they are rejected by vomiting; 
in small doses they are well supported. Dr. Galippe has given some 
to dogs, and he himself, his family, and friends have ingested these 
substances during months and years without observing the least dis- 
turbance. 

Another and far more toxic substance is arsenic, which is often 
found in wine. In 1881 four hundred persons were poisoned at Hyeres 
and Havre by arsenical wines. Again, it is in preserves that arsenic 
is mostly found. This substance is introduced because of its anti- 
fermentative properties. The gastrointestinal disturbances provoked 
by it are of frequent occurrence in Eussia, where preserved fish is 
extensively used. 

Finally, foods may contain other metals given off by cooking uten- 
sils and vessels made of pewter and nickel, which, however, do not 
seem to be dangerous. 

Among the toxic substances found in foods it is well to mention 
the aniline colours, which too often contain arsenic and which are 
used to colour wines, bonbons, and sirups. 

Of all poisonous substances added to foods, one of the most exten- 
sively used is salicylic acid. This acid, employed to prevent putrefac- 
tion, is well supported by normal persons; but it often induces grave 
manifestations in those whose kidneys are more or less markedly al- 
tered, and therefore unequal to the task of eliminating it by the urine. 

To sum up, three substances claim our attention — namely, arsenic, 
salicylic acid, and, above all, the lead salts. 

Poisoning may also be occasioned by the use of nonedible vege- 
tables or animals. We hardly need refer to the frequency of disturb- 
ances caused every year by poisonous mushrooms or toadstools, the 
action of which is due to three poisons — namely, choline, muscarine, 
and phalline. Accidents have sometimes been observed as the result 
of the use of sprouting potatoes sold as new; in fact, upon the skins 
there is found a violent poison — namely, solanine. 

It is mainly in hot countries that venomous animals are encoun- 
tered. In our latitudes the accidents are produced by the eggs of 
certain fish, such as herring, pike, molluscs, oysters, and sometimes 
certain Crustacea. 



68 INTRODUCTION TO THE STUDY OF MEDICINE 

Fish eggs provoke choleriform phenomena — that is, vomiting and 
diarrhoea accompanied by general prostration; afterward cutaneous 
manifestations appear, such as erythema and urticaria. Eecovery is 
the rule. 

The toxicity of fish is due, it seems, to their having lived in water 
containing putrefying matters, notably near coral reefs. A similar 
explanation may be given for the action of molluscs. Poisonous 
oysters are those that have lived in unwholesome surroundings — for 
example, near the outlets of sewers. Shellfish may be particularly dan- 
gerous. It was once asserted that they became toxic when they lived 
upon the sides of ships sheathed with copper. 

Even when healthy, shellfish are not good food. The inhabitants of 
Tierra del Fuego, who consume as much as 5 to 15 kilogrammes 
a day, are affected with a special hepatic cirrhosis attributed to this 
form of diet. 

Under certain circumstances the flesh of animals may become toxic 
— for example, when they are overworked. This is due either to the 
fact that overwork provokes the development of noxious substances 
or because it permits the intestinal microbes to pass into the tissues. 
Thus it is with good reason that animals destined for food are allowed 
to rest for at least twenty-four hours before they are slaughtered. 

Accidents have been provoked by the use of the flesh of animals 
receiving toxic substances. This is not always the case, however, as 
savages consume the beasts killed by poisoned arrows. Nevertheless, 
morbid manifestations may appear when use is made of the flesh of 
mammalia which have received high doses of arsenic for therapeutic 
purposes. 

In the course of diseases, and notably of infections, toxic sub- 
stances may be produced which are again met with in the tissues or 
the secretions. The flesh and milk of animals dead from indigestion, 
dropsical cachexia, various infections, and particularly puerperal fever, 
should be absolutely rejected. 

Aliments of vegetable origin may produce disturbances, either be- 
cause they come from diseased plants or because they have been invaded 
by various parasites. 

Numerous epidemics, which have been described as ergotism, feu 
Saint- Ant vine, raphania, are known to be provoked by ergot — Clavi- 
ceps purpurea. The disturbances are due to various substances, of 
which one, sphacelic acid, causes gangrene of the extremities, and 
another, cornutine, produces convulsions. The disease in man assumes 
two different types, which may either have a gangrenous or a convul- 
sive form. 

Among the alterations of cereals, it is sufficient to mention nigella 



CHEMICAL AGENTS 69 

and the wheat rot, the mixture of flour and Lolium temulentum 
(bearded darnel), and the copper green of Indian corn, which plays an 
important part in the etiology of pellagra. 

Volatile Poisons. Poisons of the Air. — Apart from alimentary 
poisons, numerous others are daily met with. Volatile poisons are 
found in the atmosphere. Confined air, vitiated by the respiration of 
several individuals, soon becomes toxic and produces indisposition and 
giddiness. When a great number of persons are inclosed in a small 
room, death may supervene. It is not merely a question of diminution 
of oxygen or accumulation of carbonic-acid gas, but one in which the 
toxic substances are of organic origin and impart to the air a well- 
known nauseating odour. 

Air may be polluted by products of combustion — for example, by 
carbonic-acid gas, which is not very dangerous, and especially by car- 
bonic oxide. Poisoning by the latter gas occurs quite frequently when 
movable stoves with slow combustion are employed. In this way as 
high as 16 per cent of carbonic oxide is produced (Moissan). When 
there is little or no draught, the slightest puff of wind drives the 
deleterious gas into the room or even into the adjoining apartments. 
This is also a source of poisoning, manifesting itself by constant 
headache, loss of memory, and anaemia, and one which, in certain cases, 
may assume an acute course, resulting in death. 

The combustion of illuminants also produces carbonic oxide. The 
oil lamp, however, gives off almost exclusively carbonic-acid gas. 

Illuminating gas is very toxic, because it contains from 7 to 20 
per cent of carbonic oxide. In Paris 150,000,000 cubic metres of it 
are manufactured. Ten per cent, say 15,000,000 cubic metres, are lost 
in consequence of defects and infiltrate the soil. On approaching a 
trench opened in the street we smell the strong odour of gas. It is no 
wonder, therefore, that the atmosphere of Paris contains 1 per 10,000 
of carbonic oxide. A much greater proportion seems to exist in apart- 
ments which, by virtue of their high temperature, draw the gas dis- 
tributed to the soil. 

The air of apartments may also be polluted by substances emanat- 
ing from paintings and tapestry. This was formerly a frequent occur- 
rence when arsenical greens were extensively used. 

Finally, as if all these causes of intoxication were not enough, the 
majority of men poison themselves by the daily use of tobacco. Every 
year 2,000,000,000 kilogrammes of this plant are consumed. In 
France the consumption exceeds 30,000,000 kilogrammes. In the 
smoking of tobacco carbonic acid, carbonic oxide, sulphuretted hydro- 
gen, hydrocyanic acid, traces of nicotine, and especially pyridic bases 
are inhaled. The last-mentioned substances are the most dangerous 



70 INTRODUCTION TO THE STUDY OF MEDICINE 

of all; they are particularly abundant in a slow and incomplete com- 
bustion — as, for example, in pipe smoking. 

Generally, the habit is quickly formed, but the abuse of tobacco 
gives rise to many disturbances — namely, diminution of memory, espe- 
cially for proper names, dyspepsia, palpitation, spells of angina pec- 
toris, which, though generally harmless, sometimes kill, as happened 
in a case reported by Dr. Letulle. 

While those who smoke are poisoned, chewers are far worse affected, 
because they ingest the various toxic substances contained in tobacco, 
notably nicotine. In those who are not accustomed to its use dis- 
turbances rapidly appear. Some persons have been seen to succumb 
from the effects of chewing half a cigar. 

In Oriental countries the smoking of opium replaces that of 
tobacco. In China they begin to smoke at about the age of eighteen; 
it is not, however, in their own homes that they give themselves up 
to this occupation; it is in more or less luxurious dens where they 
assemble or remain isolated. 

They very quickly become accustomed to the poison, and soon reach 
daily doses of from 5 to 6 grammes of the extract. The habit does 
not seem to be very pernicious ; it is much less so than the practice of 
eating opium. Eaters of opium and of theriaca, especially numerous 
in Turkey and Persia, present a premature decrepitude. 

In European countries opium is nowadays causing great ravages 
under the form of morphine injections. It is on the occasion of a pain, 
a neuralgia, or an insomnia that the first injection is resorted to ; then 
the habit is formed, and very considerable doses are reached — 0.5 to 1 
gramme, and even 4 to 5 grammes daily. 

Morphinomania is prevalent mainly among the higher classes. It 
is of very frequent occurrence in persons who can easily procure mor- 
phine. In the statistics of Dr. Pichon, comprising 66 subjects, there 
were 17 physicians, 7 students of medicine, 5 druggists, and 3 students 
of pharmacy; out of 56 women, 12 were married to physicians. 

Other poisons may be employed for the agreeable sensations they 
produce. Such are ether, cocaine, chloral, and especially hasheesh, pre- 
pared with the leaves of Cannabis indica, which is used by 200,000,000 
to 300,000,000 people in Africa, India, and Turkey. 

In Oriental Asia an inebriating beverage is prepared from a poison- 
ous mushroom — the false orange. 

Poisonings due to Occupation. — In approaching the study of poi- 
sonings due to occupation we again meet the poison with which we 
have become familiar — namely, lead. Disorders may be produced dur- 
ing the extraction of the mineral from the earth. The miners die' 
young, their average age not exceeding forty-two, and their mortality 



CHEMICAL AGENTS 71 

amounts to 18 per cent a year. In France the disorders are mostly 
observed in workers in white lead and in painters. A few years ago 
the workmen in the factory at Clichy (France) entered the hospital 
on an average of four times a year. Owing to the introduction of bet- 
ter sanitary conditions, accidents are now of much less frequent occur- 
rence. They occur mainly among painters, who are first attacked with 
lead colic and later with arteriosclerosis, paralysis, interstitial nephri- 
tis, and gout. Arteriosclerosis is a pernicious manifestation, and 
when the arteries of a young man are found to be very hard, saturnine 
poisoning can almost certainly be diagnosticated. 

Mercury, like lead, also produces grave disturbances in workmen 
employed in its extraction. The miners of Almaden, in Idria, are 
affected with a special gingivitis resulting in shedding of the teeth. 

There has been a good deal of loud talk of late, and with just 
reason, in reference to the disturbances caused by phosphorus. The 
workmen in match factories are affected with an extremely serious 
necrosis located in their lower maxillary bones. . This lesion is com- 
paratively rare to-day, owing to a better equipment of the factories, 
and especially to the use of the harmless red phosphorus, which is 
gradually tending to replace the white phosphorus. 

The combustion of coal may produce two kinds of intoxication : one 
due to arsenic, the other to carbonic oxide. Coal always contains some 
arsenic, which passes into the smoke, and, in the neighbourhood of fac- 
tories, especially of furnaces, is deposited on the soil and vegetables, 
and thus may produce poisoning in man and animals. 

Carbonic oxide is much more widely diffused. It intervenes very 
often in the habitual conditions of life. Cooks and laundresses, who 
breathe it constantly, are affected with ansemia and disturbances of 
memory. There are records of several cases of persons having been 
killed as the result of lying down near a furnace. 

There are other deleterious gases to be pointed out, such as nitrous 
vapours, chlorine disengaged in the bleaching of paper, and gases 
emanating from animal matters undergoing putrefaction. This is 
what is called mephitism. 

Accidents produced by these emanations were formerly very fre- 
quent among workers in sewers ; but to-day the ventilation of sewers is 
so perfect that the danger has disappeared. The same is true of cess- 
pools, where accidents are no longer observed except in time of repairs. 
In detaching the crusts covering the walls of sewers and cesspools, 
hydrosulphate of ammonia is disengaged, the inhalation of which 
causes rapidly fatal accidents. We may also mention the volatile 
products emanating from putrid organic matters in tanneries, catgut 
and glue factories, and the like. 



72 INTRODUCTION TO THE STUDY OF MEDICINE 

Poisoning by Drugs. — Another group of toxic causes comprises the 
medicinal substances. To say nothing of errors of dosage, there are 
poisonings caused by the impurities of certain products. Glycerine 
may contain arsenic; strontium salts are not always free from baryta. 
It should be remembered that tinctures and extracts, even when well 
prepared, are very unreliable, as they contain variable proportions of 
the active principles. Hence, the tendency is to substitute for them 
alkaloids and glucosides, which are quite definite from a chemical 
point of view; they do not, however, always manifest the same action 
as the more complex and less purified products. 

Accidents are often brought about by the use of medicine for too 
long a period. It was once believed that mercury did not produce its 
effects until it gave rise to salivation. At the present day accidents of 
this nature are no longer observed; but toxic manifestations are some- 
times produced by injections of bichloride of mercury and the long- 
continued administration of digitalis. 

It may be well to here remark that the stomach does not easily 
bear most of the medicines introduced into it. In many cases chronic 
gastritis is simply the result of abuse of therapeutic substances, and a 
good many of the troubles due to alcohol are traceable to the use of 
so-called tonic or rejuvenant wines. 

Anaesthetics have caused a certain number of deaths. Nitrous 
oxide seems to be harmless when used for very short operations and 
inhaled only a few seconds. Out of 30,000 cases reported in America 
there is not a single death. On the contrary, according to Morgan's 
statistics, chloroform has produced 34 deaths out of 100,000 cases, and 
ether only 4 for the same figure. In America these results have led 
to the substitution of ether for chloroform in surgical anaesthesia; in 
France, also, a similar tendency is now observed. 

Criminal Poisoning; Suicide; Accidents. — Poisons are frequently 
employed for criminal or suicidal purposes. Arsenic was formerly the 
one most frequently made use of. It was the basis of the Borgia 
poison, and was employed by the Marquise of Brinvilliers. Nowadays 
the progress of chemistry leads criminals to avoid the use of mineral 
poisons, since they are easily detected. The vegetable alkaloids are 
preferred, because they induce no lesions and are with great difficulty 
distinguished from cadaveric ptomaines. For this reason experts are 
often unable to arrive at a positive conclusion. 

Suicide is often committed by means of alkaloids or cyanide of 
potassium. In France the fumes of coal — that is, carbonic oxide — 
are resorted to. As a matter of fact, 185 cases of asphyxia have been 
reported as against 52 poisonings. In other countries the proportions- 
are quite different. In Italy, for example, there were 44 cases of 



CHEMICAL AGENTS 73 

asphyxia and 132 poisonings; in Prussia, 11 to 20; in England, out 
of 225 cases of poisoning there was not a single example of carbonic 
asphyxia. 

Poisons have also been utilized for judicial purposes. In Greece, 
the condemned persons were made to drink hemlock. The countries 
that we call barbarous had poisons of trial. For example, in Mada- 
gascar, on certain days the extract of Calabar bean was administered 
to 500 to 600 persons. Those who did not die were declared innocent. 
The same method was used to decide legal questions. The system, 
however, soon became modified: each adversary was represented by a 
dog; the two animals drank the poison, and the owner of the one that 
died was pronounced guilty and condemned. 

Venoms. — Venomous animals are those possessing venom glands, 
the contents of which can be exuded. These should not be confounded 
with poisonous animals. The latter contain toxic substances in their 
blood and tissues. We have spoken of them in treating of alimentary 
intoxications. 

Among the venomous animals the most dangerous are represented 
by the ophidia. All snakes are possessed of a venom gland; but in 
some of them, as in the case of couleuvres, the gland being deprived 
of an excretory duct, the poison can not be poured out. The Mont- 
pellier adder, whose gland opens at the bottom of the buccal cavity, is 
harmless for man and for animals of great size; it can kill only small 
animals, which it seizes by one of the limbs. 

The venomous species of France are three in number: the Vipera 
aspis, which must not be confounded with the asp of Egypt, the 
Vipera ammodytes, and the Pelias herus. Our (France) indigenous 
vipers are more dangerous in the south than in the north, and on the 
left than on the right bank of the river Loire. Their bite may occa- 
sion the death of an adult, and more readily that of a child ; but even 
when the bite is healed, it is in many cases followed by persistent 
neuralgia, recurring sometimes at certain seasons. 

Although serpents are not very dangerous in our (France) lati- 
tudes, they constitute a veritable evil in hot countries. In India 
20,000 persons die each year from their bites. 

The effects provoked by serpents are divided into local and general 
disturbances. Locally, oedema appears, especially marked when the 
venom is not very active; it is also observed as a result of the bites of 
our vipers. (Edema has developed sufficiently in certain regions of the 
body to mechanically cause a fatal termination. 

The general disturbances are characterized either by progressive 
asphyxia (proteroglyphes) or by convulsive phenomena (soleno- 
glyphes). 



74 INTRODUCTION TO THE STUDY OF MEDICINE 

After much discussion, it is acknowledged that snake poison con- 
sists essentially of proteid matters and albumoses. To combat its 
effects, the first thing to do is to oppose its absorption. Tying the 
bitten limb and suction of the wound are well-known procedures. 
Next, we resort to cauterization and hypodermic injection of sub- 
stances that neutralize the venom — for example, potassium perman- 
ganate, gold chloride, and, above all, calcium and sodium hypochloride. 
Lastly, it has been recognised of late that it is possible to accustom 
animals to progressively increasing doses of venom; their blood ac- 
quires curative properties and their serum has been used with success. 
The names of Phisalix, Bertrand, and Calmette are connected with 
this discovery. 

The other animals capable of producing venom are less important. 
In European countries there are the toad, triton, and, above all, the 
salamander. Among fish there are trachinidce (weever, stingfish), 
which secrete themselves in the sand, and the bite of which may pro- 
duce in bathers phlegmons and gangrene, often of very grave character. 

Venomous insects are very disagreeable, but generally not very 
dangerous. The bites of gnats, bedbugs, fleas, and ants are without 
gravity. It is estimated, however, that six to eight hornets can kill 
a man. In some cases a wasp has bitten in a region where the conse- 
quent swelling has caused death — for example, at the base of the 
tongue or in the pharynx. 

The active principle of the venom of the bee and hornet consists 
of formic acid united to a hydrocarbon — undecane, the formula of 
which is C 1:l H 24 . 

Finally, we may mention the scorpion of the south of France, the 
bite of which is of little gravity. 

Modes of Penetration of Poisons. — Poisons can penetrate our or- 
ganism in several ways. They enter mostly by the digestive canal, 
which is provided with certain means of protection. The disagreeable, 
acrid, or burning taste of certain substances causes one to expectorate 
immediately, and at the same time provokes a salivary secretion, which 
cleanses the buccal cavity. If some of the poisonous substance has 
been swallowed, antagonism is manifested in the stomach : First, by an 
abundant secretion, which hinders absorption, dilutes the poison, and 
neutralizes certain principles; next, by rejection through vomiting. 
Finally, when the poison reaches the intestine, similar phenomena are 
produced — namely, an increase of secretion and evacuating diarrhoea. 
It may be remarked, however, that the diarrhoea which supervenes in 
cases of poisoning is mainly in connection with the secondary elimina- 
tion through the mucous membrane of the intestine. 

The poison may find in the digestive canal conditions favourable 



CHEMICAL AGENTS 75 

for ics harmful action. For example, fatty matters dissolve phos- 
phorus and hasten its absorption; the hydrochloric acid of the stom- 
ach transforms calomel into corrosive sublimate, and the insoluble car- 
bonates into soluble chlorides; it also decomposes potassium cyanide 
and thus gives rise to hydrocyanic acid. Hence it is that the action 
of the substance last mentioned is less marked when the stomach is 
empty than during digestion. 

If the poison be a gas, other protective phenomena intervene. The 
odour, the pricking of the mucous membranes, the irritation that pro- 
vokes lachrymation, sneezing, or coughing, warn us of danger. These 
reactions are not constant, however, and absorption does take place. 
Gases penetrate very easily through the lungs ; even liquids introduced 
by this route can be absorbed, provided they are introduced very slowly. 

Volatile substances can also penetrate through the skin. For exam- 
ple, mercury, iodine, turpentine, and methyl salicylate are readily ab- 
sorbed in this way. Certain solids, especially when they are incor- 
porated with fats, can also pass through the integument. 

Absorption by the urinary apparatus has been a subject of much 
discussion. The prevailing opinion is that the bladder does not 
absorb; contrary results are due to the fact that too strong solutions 
have been injected, which alter the epithelial lining and abolish its 
protective function. Another cause of error capable of vitiating ex- 
perimental results is that the posterior urethra absorbs very well; a 
drop flowing from the bladder can occasion poisoning. Yery little, 
if any, absorption can take place in the ureters, but it doubtless occurs 
in the calices. In women, the vagina, and still more the uterus, may 
serve as routes of penetration for poisons; and in numerous cases 
accidents have occurred as the result of the too prolonged or contin- 
ued use of corrosive sublimate. 

The subcutaneous route is daily used in the therapeutic introduc- 
tion of medicines. Absorption is the slower the thicker the subcu- 
taneous fatty tissue is, and it varies also according to regions. The 
different parts of the body may be classified as follows: First, the 
temples and cheeks; second, the epigastric region, the inner surfaces 
of the thorax, the external surfaces of the arms and thighs, the foot, 
and, last of all, the back. From a practical standpoint these results 
are evidently very important. Absorption can also take place in ex- 
posed mucous membranes, such as the conjunctiva, and in serous 
membranes, such as the pleura or the peritoneum. 

Among the conditions antagonizing or favouring absorption we 
must note certain modifications of a physical order. A decrease of 
pressure upon the integuments retards absorption. This is what is 
realized by suction or by dry cupping. If, however, pressure in the 



76 INTRODUCTION TO THE STUDY OF MEDICINE 

abdominal cavity be increased, the passage of colloids, like the albu- 
mins, is hindered, while that of crystalloids is enhanced. This result, 
which has greatly surprised certain authorities, is altogether in accord- 
ance with physical laws. The same effects are observed when a liquid 
is made to pass through a porcelain filter: the increased pressure 
hastens the passage of the water and of the salts dissolved in it, but 
causes a dissociation of albumins, which are not carried off by the cur- 
rent but retained on the filter. 

Since the time of Magendie it is admitted that bloodletting 
favours absorption, while intravenous injections of salt water delay the 
passage of substances by increasing the mass of blood. These results 
are exact, although far more complex than was believed. The effect of 
injections of water is notably to modify the reactional power of the 
nervous centres and the secretory role of the kidneys. This is what 
renders the problem so difficult and the interpretations so very delicate. 

The absorption of toxic substances is determined chiefly by the 
venous system. Magendie has perfectly demonstrated this by an ex- 
periment which has become classical. He divided the thigh of a dog 
and united the two ends of the severed artery and vein by glass tubes ; 
he introduced poison into the paw thus connected with the rest of the 
body, and toxic manifestations were produced. The poison could not 
have penetrated except by the blood vessels, since the lymphatics no 
longer existed. 

Transformation, Elimination, and Accumulation of Poisons. — After 
reaching the blood, poisons act differently, according to the manner 
of entrance. If they enter through the digestive tract, they pass into 
the mesenteric and portal veins and arrive first at the liver. Placed 
as a barrier in the path of all substances coming from the gastro- 
intestinal apparatus, the liver exerts on them a selective action; it 
allows some to pass on, retains others, and, after having stored them 
up for some time, permits them to gradually pass again in harmless 
amounts ; it eliminates some of them through the bile, and, finally, it 
submits many others to chemical transformations, depriving them of 
their toxicity. These modifications are especially brought to bear upon 
the alkaloids, so that a poison loses about half of its toxicity in pass- 
ing through the hepatic gland. Here, then, is an important protective 
role to which we shall more than once refer. 

When it has passed through the liver, or when it has penetrated 
directly through the skin or subcutaneous tissue, the poison reaches 
the vena cava, passes through the heart, and arrives at the lungs. 
Here is another protecting organ. It acts upon certain alkaloids, no- 
tably upon strychnine; but it especially eliminates volatile substances. 
Sulphuretted hydrogen, for instance, which is very toxic when inhaled, 



CHEMICAL AGENTS 77 

can be introduced by the stomach or the rectum without inconvenience ; 
it is exhaled by the air as fast as it penetrates. Phosphorus is also 
eliminated by the lungs, and imparts to the expired air the property 
of luminosity in the dark. The other gaseous substances follow the 
same route, since it is possible to notice them by the characteristic 
odour of the breath. 

After passing the pulmonary barrier, poisons arrive at the left 
heart, and from there pass on through the aorta to be distributed to 
the different parts of the organism. They reach the nervous system, 
where they produce the principal disturbances due to their action. 
Part of the poison, however, passes through certain protective organs, 
such as the sanguineous vascular glands; another part encounters 
organs which throw it out. Poisons thus pass into secretions — sweat, 
milk, tears, and especially the urine. 

The .kidney, in fact, represents the principal route of elimination 
for the majority of toxic substances. Finally, a certain amount of 
poison may return to the stomach and intestine by the mesenteric 
arteries and cceliac axis, and be eliminated by the glands of the digestive 
canal. Morphine, for example, passes into the gastric secretion; there- 
fore, in cases of poisoning by this alkaloid, it is well to wash out the 
stomach even when the poison is introduced by the hypodermic route. 
The poisons passing out by way of the intestines may produce diar- 
rhoea and sometimes alter the mucous membrane, which is then placed 
at the mercy of the numerous intestinal microbes. Thus a gangrenous 
enteritis results under the influence of corrosive sublimate. It is a 
lesion induced by the elimination of mercury and determined by the 
intestinal bacteria. 

Certain conditions intervene to favour or hinder the elimination of 
poisons. In children, the kidneys work with extraordinary energy, 
and this is why poisons which can be eliminated by the urine are so 
well borne by children. The same doses of salicylate of sodium given 
to an adult can be given a child of six years. 

In the old, on the contrary, elimination is slow. Much caution, 
therefore, is to be exercised in the administration of active medicines to 
the aged. 

Finally, elimination is modified during the course of various or- 
ganic affections — for example, in nephritis, the urinary function being 
insufficient, active substances easily provoke disturbances. 

Poisons accumulate mainly in two parts of the economy — namely, 
in the liver and the osseous system. The analyses of toxicologists 
teach us that arsenic, lead, and mercury are able thus to remain for 
years. Hence the possibility of disturbances breaking out long after 
the use of a poison has been suspended. Kussmaul reports that two 



78 INTRODUCTION TO THE STUDY OF MEDICINE 

persons developed salivation on the occasion of a sulphur treatment 
four and twelve months respectively after having ceased the employ- 
ment of mercury. 

The possibility of these accumulations should not be lost sight of 
in practising therapeutics ; doses perfectly well borne at first may pro- 
duce disturbances at the end of a few days; such is the case with 
digitalis. 

Toxic Equivalents: their Variations. — The considerations we have 
presented already explain that a toxic substance does not always pro- 
duce the same phenomena in the same doses. 

In the first place, there are variations dependent upon the species. 
Take nicotine, for example. The fatal dose of this alkaloid, reduced to 
the proportion of 1 kilogramme of animal, is represented by the fol- 
lowing figures : 35 milligrammes for the frog, 12 milligrammes for the 
guinea pig, 7 milligrammes for the rabbit, 5 milligrammes for the 
dog, and 0.5 milligramme for man. As a rule, the higher the being 
is in the animal scale, the keener is its susceptibility. 

In the next place, variations according to races are to be taken 
into account. Darwin furnishes numerous examples : the white sheep 
and hog are more sensitive to certain poisons than those of dark col- 
our. In man, morphine calms a European, while it excites and drives 
a Malay to homicide. 

Fatal doses vary also according to age-, more poison is required, 
weight for weight, for killing a child than an adult, and especially an old 
man. The influence of sex is quite evident in the following figures, 
given by Preyer: To kill a male guinea pig 8 milligrammes of curare 
are required; for a female, 13 milligrammes; and in the case of a preg- 
nant female, as much as 17 milligrammes. 

A condition of another order is represented by the temperature of 
the body. Thermal elevation favours the action of poisons. The 
surrounding temperature may have variable effects; it renders the 
organism more sensitive to convulsive poisons, but facilitates the 
elimination of certain substances. If we give the same dose of chloral 
to three guinea pigs, we see the one left in the open air die in four 
hours; the second, wrapped in cotton, will survive after a sleep 
of twenty-four hours; the third, placed in an oven, will recover in 
seven hours. By cooling certain animals, and by heating others, we 
can further vary the fatal doses. 

The state of fasting or digestion should also be taken into con- 
sideration, and likewise the integrity or lesions of various organs, 
particularly those that are concerned in the transformation and elimi- 
nation of toxic substances. Finally, there exist particular idiosyn- 
crasies, resulting from a series of inappreciable causes which impart 



CHEMICAL AGENTS 79 

to beings a resistance and predisposition impossible to determine in 
advance. 

It may be understood how difficult it is to exactly establish, the 
fatal dose of a substance. A great many attempts have, however, been 
made in this direction, and have already led to results of much inter- 
est. By operating on animals and injecting poison into the veins, it 
has been possible to determine the deadly dose. Dr. Bouchard pro- 
poses to designate the quantity of poison capable of killing a kilo- 
gramme of animal by intravenous injection as the toxic equivalent. 
It is evident that the toxic equivalent is applicable only to the species 
on which the operation has been made, and that it would not be exact 
to transfer the results from the animal to man. We can only obtain 
interesting indications. 

If figures determined in experimenting upon animals are fairly 
concordant, effects observed in man are far more variable. Thus, in 
certain cases, 0.3 gramme of extract of opium has proved fatal; in 
other cases, 1.5 gramme has been endured. The results are the same 
for morphine: 0.4 may kill and 2 grammes may not cause death; 1 
centigramme of atropine sulphate generally represents a deadly dose, 
whereas some persons have tolerated 25 or 30 centigrammes; and 
with cocaine, 4 centigrammes have killed in one case; 1.25 gramme has 
not done so in another. 

Habit. — Finally, it should not be forgotten that one soon becomes 
accustomed to certain poisons. Tobacco, alcohol, and morphine, which 
first arouse painful reactions, are very well borne after some time and 
even seem to become indispensable to life. A familiar illustration is 
afforded by the history of the amoeba, which can gradually be habitu- 
ated to water containing 2 per cent of sea salt; it becomes so accus- 
tomed to the new conditions that it perishes when again brought back 
into ordinary water. Under the influence of poisons frequently intro- 
duced, a modification of cellular nutrition is effected, with consequent 
humoral changes : the humours become antitoxic in nature — i. e., they 
acquire the property of neutralizing the noxious effects of substances 
to which they have become habituated. Here a new field is opened to 
therapeutics. 

Anatomical lesions of Toxic Origin. — In producing functional 
troubles, poisons gradually modify the structure of cells — i. e., give 
rise to anatomical lesions in them. They may produce local manifes- 
tations, pus, or sloughing. In other cases they induce alterations in 
organs or tissues. Among these, some are common manifestations: 
hemorrhages, muscular ruptures provoked by contractures and convul- 
sions, emphysema due to respiratory disorder, and subpleural or sub- 
pericardial ecchymoses induced by asphyxia. Others are to be con- 



80 INTRODUCTION TO THE STUDY OF MEDICINE 

neeted directly with the action of poisons. If it is true that functional 
disturbance always precedes the anatomical lesion, it is easy to under- 
stand that the poison will exert its effects first upon the most clearly 
differentiated elements — i. e., upon those that act effectively. The 
lesions of connective tissue will be but secondary. In the kidney, for 
instance, it is always. the epithelium that is first attacked; in the liver, 
the hepatic or biliary cells; in the spinal cord, the great nerve cells. 
If among these affected cells some should succumb, the defect thus 
produced will be supplied by connective tissue. Thus what is called 
sclerosis is developed. The function of the connective tissue not being 
deranged, we can not conceive it io be the seat of primary lesion. 
Its development is a phenomenon of reparation, comparable to a 
cicatrix. 

Finally, in cases of chronic intoxications, nutritive modifications 
are produced, sometimes finding expression in emaciation (morphino- 
mania), sometimes in obesity (alcoholism), and in still other cases in 
some curious phenomenon, as uricsemia and gout (saturnine). 

The various disturbances provoked by toxic agents may be trans- 
mitted to descendants. It is thus that beings come into the world 
with organic taints and nutritive vices ; and, as the morbid impression 
will have acted on young and easily impressionable cells, the disorders 
acquired by parents will often be found exaggerated in their offspring. 



CHAPTER Y 
ANIMATE AGENTS 

Parasites and infectious agents — Definition of infectious diseases — History — Spon- 
taneous generation, fermentations — The work of Spallanzani, Davaine, Pas- 
teur — Division and cultivation of infectious agents — Bacteria: their classifica- 
tion, their variability. 

The animate agents are usually divided into two groups — parasites 
and infections agents. 

Some writers have thought that natural history could be taken as 
a basis for this distinction. According to them, infectious diseases 
are those caused by bacteria. This conception,, however, seems scarce- 
ly admissible, for the group of infectious diseases was created before 
the discovery of bacteria, and hence was of necessity established upon 
the data of clinical observation. It is only by comparing the morbid 
processes, by taking into account the conditions of their development, 
the manifestations they have presented, and the evolution they have 
followed, that it has been possible to draw closer together certain 
diseases and group them. The bases of the classification, therefore, 
have been symptomatic. It was and still is the only possible classi- 
fication. Since the apparent signs are to be traced to hidden occur- 
rences, it has been and it always will be necessary to start from what 
we see — namely, from clinical manifestations — and it is only by de- 
duction that the cause of observed disorders can be affirmed. 

When the animate nature of pathogenic agents was discovered, it 
was desired to establish a relation between infectious diseases, as they 
have been defined, and the microbes which were disclosed. But such 
relations do not exist. Malarial fever, which everybody classes among 
infections, is due not to a bacterium, but a sporozoid. The type of 
infectious diseases, tuberculosis, seems to depend upon a relatively high 
fungus or a streptothrix akin to actinomyces. Yet no one would 
dare maintain that malaria and tuberculosis must be thrown out of 
the class of infectious diseases. 

81 



82 INTKODUCTION TO THE STUDY OF MEDICINE 

We therefore conclude that infectious agents may belong to classes 
other than bacteria, and that there is no constant relationship between 
their taxonomic position and their action on living beings. 

What, then, is the difference between parasitic and infectious 
agents ? 

A chief distinction is furnished by the way in which the two kinds 
of agents act toward the individual upon whom they live. The para- 
site spares his host ; it does him the least harm possible ; it draws ex- 
actly what it needs for its own subsistence ; it understands that it is to 
its own interest to preserve for the longest possible time the individual 
upon whom it lives. 

The infectious agent does not take all these precautions. It acts 
with brutality: develops rapidly, tends to invade the entire organ- 
ism, disturbs its functions, excites very intense reactions. It engages 
in a terrible struggle, the issue of which varies according to a number 
of secondary circumstances. 

The parasite is satisfied with the corner where it vegetates ; it grows 
slowly, expands very little, and it hardly, if ever, invades the economy; 
and if, at a certain moment, it causes death, it is, as it were, acci- 
dentally, unwittingly. Example: The intestinal worm when « it makes 
its way into the air passages. In this way the parasite, satisfied 
with little, is easily supported; it does not give rise to violent reac- 
tions; often it remains even unnoticed. It may, however, grow, and 
when its volume becomes considerable, it may produce various dis- 
turbances. Such is the case with a hydatid. But the phenomena pro- 
voked here are due to compression; they are of a mechanical order. 
On the contrary, infectious agents act chiefly by the fermentations 
which they produce and by the toxic substances which they engender. 
There precisely lies the chief difference. No doubt, as in all distinc- 
tions, this is not an absolute one. Parasites also produce toxic sub- 
stances ; some are found in the liquid of hydatids. It is always a ques- 
tion of more or of less. But, with parasites, intoxication is reduced to 
a minimum; with infectious agents, it becomes predominant and ex- 
plains all the reactionary phenomena. Infectious diseases may there- 
fore be defined, "Diseases developed under the influence of toxines 
produced by certain parasitic agents." 

Infection, then, is nothing else than a chapter of intoxication. 

History. — Three terms characterize all infections : an animate 
agent, a fermentation, an intoxication. These three terms are en- 
countered in the writings of the most ancient observers. 

From Varro and Columelle to Linnaeus, only beings relatively high 
in organization were considered capable of producing infectious dis- 
eases. This gross parasitism which attributed a pathogenic action to 



ANIMATE AGENTS 83 

worms, insects, or arachnidae, attained its height with the theories of 
Raspail on sarcoptogenesis. 

With the idea of comparing viruses to poisons evolved simultane- 
ously, typhic or paludal intoxication was spoken of, though without 
attaching a very precise meaning to these expressions. There was 
only a tendency to consider certain miasms as volatile poisons. 

Finally, since Rhazes, who likened smallpox to the fermenting 
must of grapes, many physicians — Hoffman, Braconnot, Bouillaud — 
compared the infectious to the fermentative process. It was the com- 
parison of an unknown phenomenon with another which was no better 
known. Up to recent years the nature of these two great processes 
was completely obscured, and whenever a happy chance permitted the 
discovery of a living being in a diseased organism, in putrescent mat- 
ter, or in a fermenting liquid, it was simply supposed to be a case of 
spontaneous generation. 

The first author who revolted against the nefarious yoke of the 
belief in spontaneous generation, which had dominated since Aristotle, 
was a naturalist of the seventeenth century, F. Redi. The experiment 
which he realized, no matter how childish it may seem to-day, pos- 
sessed at that epoch vast importance. Redi established the fact that 
the larvae of flies were not born spontaneously through putrefaction 
of meat. By means of a gauze, he prevented the insects from deposit- 
ing their eggs, and henceforth the larvae did not develop. 

A few years later, in 1678, van Leeuwenhoek, examining vegetable 
infusions, observed the presence of microscopic beings, which Wris- 
berg, in order to recall their origin, named infusoria. Van Leeuwen- 
hoek understood that these beings were not born by the decomposition 
of matters, but that they proceeded from pre-existing germs, spread 
in the atmosphere. This very same idea was again taken up in the 
following century and developed, in a series of admirable studies, by 
Spallanzani. Stimulated by numerous attacks directed against him 
by Needham, Spallanzani multiplied his researches and established the 
fact that there is no fermentation when the liquids are protected from 
air. This great discovery was confirmed by Schultze and by Schwann. 
Finally, in 1837, Cagniard-Latour showed that during alcoholic fer- 
mentation yeast increases and multiplies absolutely like a vegetable. 

Yet, despite the observations made by van Leeuwenhoek, Spallan- 
zani, and Cagniard-Latour, the question of fermentations remained 
very obscure. The progress of discoveries was arrested by the belief in 
spontaneous generation, which still persisted, and by the false theories 
that had been accepted upon Liebig's authority. The fermentative pro- 
cess was attributed to a particular condition of matter, exercising 
some kind of a catalytic action. 



84: INTRODUCTION TO THE STUDY OF MEDICINE 

It was then that Pasteur undertook the study of the problem. 
Completing the researches of Spallanzani, he demonstrated that innu- 
merable germs are hovering in the atmosphere, and that, falling into 
certain liquids, if they there find the conditions favourable for their 
development, they determine fermentation. Pasteur then conceived 
the brilliant idea of isolating and cultivating these germs, and he thus 
succeeded in describing successively, in 1857, the lactic ferment; in 
1860, the alcoholic ferment; in 1861, the butyric ferment. This 
last ferment differed from all beings known up to that time by 
the fact that it lived without oxygen; it was the first example of 
anaerobiosis. 

These works aroused numerous protestations on the part of chem- 
ists. Physicians took no interest in them, as they failed to see the 
applications which they could make of them to medicine. Only one 
man saw clearly: that was Davaine. 

In 1850 Davaine discovered the first pathogenic microbe that had 
ever been seen. Examining the blood of sheep dead from anthrax, he 
discovered small motionless and refractive rods, of which he did not 
suspect either the nature or the meaning, and to which he only attrib- 
uted a diagnostic value. These same elements were again found in 
1855 by Pollender, and in 1857 by Brauell, who observed them in the 
blood drawn from the living animal. In 1860 Delafond, by a spark 
of genius, determined that these rods were vegetables. He made some 
attempts to cultivate them in the blood, saw the rods grow in the form 
of filaments, and it even occurred to him to look for spores, which he 
failed, however, to bring to light. 

The following year appeared Pasteur's work on butyric ferment. 
Its perusal threw light on Davaine's mind and brought him back 
to the study of the vegetable which he had seen in the blood of animals 
suffering with anthrax. He learned that infectious diseases were pro- 
duced by microbes, just as are fermentations. He undertook a series 
of researches, the results of which he published in 1863. This brought 
down upon him an avalanche of criticism and gave occasion to con- 
tradictory experiments. Signol, Leplat and Jaillard, Sanson and 
Bouley, to cite only the principals, endeavoured to prove that the bac- 
teridia of Davaine are not found exclusively in the blood of animals 
affected with anthrax ; that they had no specific value, and that putrid 
blood swarmed with similar microbes, equally capable of killing 
animals. 

Davaine had no trouble in refuting these objections. He showed 
that his adversaries were mistaken; that they confounded anthrax 
and septicaemia, and that the microbes found in putrid blood are the 
agents of a special process of which he made a remarkable study. 



ANIMATE AGENTS 85 

V 

We can not help admiring Davaine when we think of the work 
achieved by him under the most unfavourable conditions ! A simple 
practising physician, Davaine could only work in his small property 
in Garches or in caves placed at his disposal by a friend. It was 
under these defective and discouraging conditions that Davaine took 
up and solved the principal problems relating to infectious diseases. 
Is it not really a great pity that such discoveries were not appreciated 
enough to give their author an official position or to create for him a 
laboratory ? 

However, the impulse was given. On all sides the study of the 
pathogenic problem was taken up. It was Villemin who first estab- 
lished, in 1866, the inoculability of tuberculosis. In 1867, Chauveau 
demonstrated that in virulent liquids the active part does not pass 
through a porcelain filter. In 1872, Coze and Feltz published a series 
of researches on infections, and had the merit of perceiving the strepto- 
coccus of puerperal fever. Simultaneously, in Germany, Cohn and 
Nageli isolated a series of saprophytic microbes and indicated the 
means of cultivating them. In 1875, Koch entered upon the scene 
with the discovery of the anthrax spores. 

Prepared as he was by his researches on fermentations, Pasteur 
undertook the study of diseases. He first took up the lower beings 
and published researches on the diseases of silkworms highly instruc- 
tive for human pathology, but to which the medical world paid no 
attention. Passing then to the diseases of mammalia, Pasteur under- 
took the study of anthrax. In 1877, he supported with his authority 
Davaine's researches, and made known the means for the cultivation 
of pathogenic bacteria. He thus created the fundamental methods of 
bacteriology, a field which Koch was soon to perfect by the use of solid 
media. These procedures, so simple and so sure, permitted the isola- 
tion successively of a whole series of pathogenic agents, and rendered 
it possible to obtain them in pure cultures and to reproduce in animals 
the diseases observed in man. 

The first discoveries gave rise to vigorous opposition; but, little 
by little, the adversaries were silenced, and were forced to yield to 
the accumulating works and to bow before the achieved results. In 
less than twenty years this great scientific revolution was accomplished, 
with Davaine as its pioneer and Pasteur as its artisan. 

Division of Infectious Agents. — The first bacteriological discover- 
ies led to a conception which for a moment nearly impeded all prog- 
ress. By an induction easy to understand, it was believed that every 
disease was caused by a well-defined, special microbe. We know to-day 
that this is not so, and we can in this regard formulate the two fol- 
lowing laws, which govern the whole history of infectious diseases : 



86 INTRODUCTION TO THE STUDY OP MEDICINE 

The same microbe may produce diseases the clinical manifestations 
of which are absolutely different. 

A disease, clinically well defined, may be produced by different 
microbes. 

Let us take, for example, a widespread microbe, streptococcus: it 
produces pus, erysipelas, septicaemia, pysemia, lymphangitis, pseudo- 
membranes, gangrene, visceral inflammations, etc. 

Reciprocally, a well-defined affection, like broncho-pneumonia, may 
be due to most varied microbes, as streptococcus, staphylococcus, pneu- 
mococcus, pneumobacillus, coli bacillus, etc. 

Therefore there is no necessary and constant relation between dis- 
eases as they are clinically determined and pathogenic agents as they 
are made known by bacteriology. 

Such results must not surprise us; they do not differ from those 
observed in studying other pathogenic agents, notably the poisons. 
Alcohol, for instance, produces inebriation, delirium tremens, hepatic 
cirrhosis, pachymeningitis, peripheral neuritis, etc. It is always the 
same poison, except that it acts under different conditions. 

On the other hand, the manifestations just mentioned may be ref- 
erable to most diverse toxines; peripheral neuritis, for instance, may 
be engendered by lead as well as by alcohol. 

We are thus led to admit that, from a medical point of view, in- 
fectious agents may be divided into two groups : specific and nonspe- 
cific agents. 

The former are those which determine diseases always similar to 
themselves, or at least diseases which present common characteristics 
enough to enable us to relate to each other the various clinical forms ; 
such is the case with typhoid fever, anthrax, glanders, and tuberculosis. 

The second group, numerically the more important, comprises 
agents apt to produce the most dissimilar clinical types. They are, as 
Peter said, all-round microbes (microbes a bout faire). Let us take, 
for instance, Staphylococcus aureus. According to its localization, it 
will produce a boil, an osteomyelitis, an ulcerative endocarditis, a sep- 
ticaemia, a pyaemia, etc. ; the diverse manifestations produced by it are 
dependent both upon the general soil where it evolves and upon its 
localization. 

We have already said that we must not take as synonyms the 
expressions "infectious agents" and " microbic agents." Infectious 
diseases may be produced by beings which are very different from the 
standpoint of natural history. 

They may be classed in four categories : 

1. Bacteria, which belong to the family of algae, and come under 
the group of schizomycetes (Nageli), or, better, schizophycetes. 



ANIMATE AGENTS 87 

2. Pathogenic Fungi, or hyphomycetes, of which the most inter- 
esting are represented by aspergillus and streptothrix. The latter form 
a transition between fungi and bacteria. Actinomyces is arranged here, 
and there is a tendency now to include also the agent of tuberculosis. 

3. Pathogenic Yeasts, or blastomycetes, which, however, could 
find their place in the group of fungi. 

4. Animal Microbes, and particularly protozoa. 

Cultivation of Infectious Agents. — The majority of these patho- 
genic agents may be isolated and cultivated on artificial liquid or solid 
media. 

As liquid media, mineral solutions have been used, for which a good 
many formulae have been given since the first researches of Cohn and 
Nageli. Vegetable infusions may also be employed, and liquids pre- 
pared with hay, straw, barley, malt, etc., are often utilized. In most 
cases we have recourse to animal substances; we use bouillon with or 
without peptone. Preference is sometimes given to natural products, 
such as defibrinized blood, serum, urine, milk, acetic fluid, aqueous 
humour, the white of egg, and the like. 

The second procedure consists in cultivating microbes on solid 
media. A vegetable or animal infusion is taken and solidified by the 
addition of gelatine ; this solid medium liquefies "at 23° C, and there- 
fore it can not be placed in the incubator. In order to make cultures 
at a temperature of 37° to 38° C, we replace gelatine by another sub- 
stance, agar-agar. 

In the case of strongly albuminous natural liquids it suffices, in 
order to solidify them, to coagulate them by heat. This is what is done 
with blood serum, defibrinized blood, and the white of egg. 

Finally, we frequently utilize slices of cooked vegetables, such as 
potatoes, carrots, artichokes, etc. 

The media may also be modified by the addition of various sub- 
stances — e. g., glucose, glycerine, aniline colours, and tincture of litmus. 

When the agent under study has been deposited on the medium 
adapted to it, the culture may be left alone at the surrounding tem- 
perature. Usually it is put into incubators regulated at 37° or 38° C. 

According to the element under observation, cultures are made with 
free access to air or protected from air. In the latter case use is made 
of tubes from which the air has been extracted by means of a pump, 
or which have been filled with an inert gas. It is often sufficient to 
cover the medium with a layer of sterilized oil, or simply to deposit 
the microbe at the bottom of a tube containing a sufficient amount of 
agar-agar. The air does not penetrate into the deep parts. Finally, 
one may resort to an arrangement which permits the absorption of 
oxygen by pyrogallic acid. 
7 



88 INTRODUCTION TO THE STUDY OF MEDICINE 

Division of Bacteria. — The various procedures above indicated per- 
mit the cultivation not only of bacteria, but also of the majority of 
fungi and yeasts. In general, cultures are not attended with success 
in the case of animal microbes, except, perhaps, the amoebae. 

In order to determine what kind of microbes we are dealing with, 
we must take into account a whole series of characteristics. With few 
exceptions, the appearance of the colonies upon a medium is not suf- 
ficient ; we must multiply and vary the cultures, and complete, by micro- 
scopic examination and inoculation in animals, the first results thus 
obtained. 

Since the researches of Weigert, Koch, and Ehrlich, it is customary 
to stain microbes with aniline colours. The reactions produced by col- 
ouring matters may serve in diagnosis. There are microbes which re- 




o u 
A, 



CD 
Co 0° 

B 



89 






Yiq. 4.— Schematic aspect of the various species of bacteria. A, monococci ; B, diplococci ; 
C, streptococci; D, tetracocci; JS, staphylococci; F, bacilli; £, bacteria; H, leptothrix; 
/, cladothrix ; J, spirilla. 

tain them strongly; others part with them readily. Several are easily 
discolorized by alcohol, after the action of iodo-iodide reagent; this is 
what constitutes Gram's method. 

Microbes have been classified most often after their morphological 
aspect. Now, when less importance is attached to morphology than 
formerly, the old classifications have been simplified. There are now 
but two great groups admitted : sphero-bacteria, called cocci or micro- 
cocci, and staff-shaped bacteria, called bacilli or rods. 

Micrococci are small spheres, which are generally nonmotile, unpro- 
vided with vibratile flagella, reproduced by fission, and bear no spores. 

Bacilli are small rods, often motile and provided with vibratile 



ANIMATE AGENTS 89 

cilia, reproduced by fission and often by sporalation. Generally spol- 
iation occurs in the form of endospores, seldom of arthrospores, which 
are distinguished by their remarkable refracting power and their great 
resistance to colouring reagents. 

According to their groupings (Fig. 4), micrococci have been 
divided as follows : 

1. Mono cocci — presenting themselves under the form of small 
spheres well isolated from each other. 

2. Diplococci — consisting of two cocci, joined. 

3. Streptococci — more or less long chains, consisting of 3 or 4 to 
40 or 50 individuals; their appearance may be compared to a pearl 
necklace. 

4. Tetracocci or tetragenus — formed of four cocci or tetrads, and 
placed on the same plane. 

5. Sarcina? — in which the division is made in all directions. These 
are small cubes having four cocci on each side. 

6. Zooglea — represented by masses of micrococci united by a sort of 
jelly. 

7. Staphylococci — a variety of zooglea presenting the aspect of 
grape bunches. 

Bacilli have frequently been divided into three groups: 

1. Bacilli, properly so called — slender rods and often motile. 

2. Bacteria — larger rods. 

3. Bacteridia — large and nonmotile rods. The anthrax bacillus 
comes under this group. 

However, though we say " anthrax bacteridium," the distinctions 
that we have just indicated are no longer admitted to-day. The gen- 
erally admitted classification is as follows : 

1. Bacilli, properly so called. 

2. Leptothrix — long, segmented filaments. 

3. Beggiatoa — long, thicker filaments. 

4. Cladothrix — bacteria which appear branched. In reality the 
branchings are false. The elements, being born by fission, remain 
close side by side at their points of origin, the primitive element con- 
tinuing to grow. One might believe, at first sight, that there is a 
lateral ramification. 

5. Spirilla — curved bacteria receiving sometimes the name of 
vibrios, when the element is bent, and spirilla when the microbe repre- 
sents a rolled filament. The term spirochceta, applied to long and flex- 
ible spirilla, is now abandoned. 

Variations of Bacteria. — The classification of bacteria is, as can be 
seen by these examples, based entirely on their forms. It would have 
been a good one if the forms were invariable. But such is not the case. 



90 INTRODUCTION TO THE STUDY OF MEDICINE 

The doctrine of monomorphism, supported by Cohn, had to give way 
to the conception of polymorphism developed by Nageli and supported 
by Pasteur. It is to-day a familiar truth that the form of bacteria, 
especially of bacilli, is being constantly modified ; the same is - true 
of other pathogenic vegetables. Streptothrix and yeasts present, ac- 
cording to a great number of circumstances, very marked variations. 

In this respect, two orders of modifications are to be distin- 
guished. 

Microbes change their form at certain periods of their develop- 
ment; such is the case with the colon bacillus, which presents itself 
first under the form of filaments, then of rods, and finally of oval ele- 
ments, short enough to simulate micrococci. Modifications no less 
notable are observed in old cultures where certain elements, often 
swollen into a club shape, constitute what are called involution forms. 

In other cases, variations are produced because the medium has 
been changed. The anthrax bacillus forms small rods in the blood 
of animals and long filaments in culture media; soon these filaments 
inclose spores, while these organs of reproduction are never met with 
in the blood. Likewise, different forms are obtained by sowing 
microbes in diverse media, such as bouillon, agar-agar, or potato. 
Finally, adding small amounts of antiseptics, we may observe the 
development of new forms, which often do not at all resemble the 
primitive stock. 

This polymorphism, though very well marked, is not surprising. 
It is a particular case of the great laws of evolution. The surrounding- 
medium having changed, the being could not remain identical. Simi- 
lar modifications are observed with certain yeasts, which, according 
to the media, appear under the form of oval elements or mycelial fila- 
ments. The same variations are also noted in the case of actinomy- 
cetes, which at one time are composed of masses of radiate filaments 
terminating in club form, and at another arranged in the forms of 
small rods similar to bacilli. A still more curious example is furnished 
by the tubercle microbe, which under certain conditions offers morpho- 
logical characteristics 'that have sometimes led to its being considered 
a streptothrix akin to actinomyces. 

Certain bacteria possess the property of being surrounded by a cap- 
sule. This is the case with pneumococcus, pneumobacillus, and tetra- 
genus. But this characteristic is not any more constant than the 
others. Bacteria lose their capsules in certain media; some may ac- 
quire them accidentally, as does, for instance, the streptococcus. 

The sporogenic property is not any more fixed. By certain con- 
trivances there are created new races, called asporogenic. The bac- 
terium of anthrax, after being cultivated in bouillon to which chromate 



ANIMATE AGENTS 91 

of potassium is added, loses its sporogenic property in the following 
generations, even if it be replaced in ordinary media. 

Under the impulse of Pasteur's ideas, it was thought that a basis 
of classification could be found in the study of fermentations pro- 
duced by microbes. Many objections may be made to this view. Let 
us take, for instance, the colon bacillus. Here is an agent which 
engenders lactic acid and indol. There exist microbes having the 
same biological characters, but which do not produce these fermenta- 
tions. Chemists look upon them as different species, and the majority 
of bacteriologists make of them simple varieties, under the name para- 
colon bacilli. What gives a certain amount of support to this opinion 
is that modifications may occur in the fermentative power of certain 
samples; there are cases on record where a paracolon bacillus, after 
a series of cultures in artificial media, has acquired the ability to 
produce lactic acid and to coagulate milk. 

Nor can we classify microbes on the basis of their chromogenic 
function. Some of them produce various pigments — green, red, yel- 
low, violet; but, by placing them under unfavourable conditions, by 
submitting them to high temperatures, to the influence of compressed 
oxygen, or to the action of antiseptic substances, it is possible to 
suppress this function, sometimes permanently. 

A final characteristic remains, and the most important from a 
medical point of view. Microbes have been divided into three groups — 
saprophytes, parasites, and pathogenies. Saprophytes are those which 
multiply on dead matter; parasites exist on living beings, without 
notably harming them. The pathogenies provoke the development of 
diseases. This distinction is not yet absolute. Certain saprophytes, 
falling accidentally on a living organism, may, so to speak, become 
accustomed to this new medium and rise to the rank of parasites or 
of pathogenic agents. The parasites that we bear on our bodies are 
equally modified by a great number of circumstances. The exaltation 
of our habitual guests is one of the principal causes of infectious 
diseases, and, vice versa, the most virulent agents lose, at certain 
moments, their pathogenic action and revert to the rank of parasites 
and saprophytes. It is exactly upon these functional variations that 
the great principle of the attenuation of viruses and of vaccination is 
based. 

Lastly, we must remember that cultures are never homogeneous. 
Microbes, as living beings, have their individuality. In any given col- 
ony there are always certain individuals more fully developed or more 
resistant than others. This explains why small doses of antiseptics 
do not kill all microbes at the same time, but only decrease their 
number; it is the weakest that perish. In the same way a colony of 



92 INTRODUCTION TO THE STUDY OF MEDICINE 

chromogenie microbes largely spread on a nutrient surface will give 
birth to new colonies, some of which will be deeply coloured and some 
colourless. The same remarks are applicable to pathogenic properties. 
Functional variations, attenuations, and exaltations are individual 
modifications. 

We shall therefore conclude that, in order to determine the species 
of a microbe and its place in the classification, we must pursue very 
long investigations, because we must take into account a whole series 
of characters. We must thoroughly study its morphology, its reac- 
tions toward colouring reagents, the appearance of its cultures on 
various media, its fermentative properties, and its pathogenic action. 
It is only upon the ensemble of the properties of a microbe that a con- 
clusion can be founded. Still, in certain cases, it will be impossible to 
decide and to recognise the species under examination. 



CHAPTER VI 
ANIMATE AGENTS (Continued) 

The animal parasites — The vegetable parasites — The infectious agents — Bacteria: 
their division into specific and nonspecific — Phycomycetes — Mycomycetes — 
Protozoa — Medical classification of infectious agents. 

Without having the intention of describing, even briefly, the para- 
sites and infections agents actually known, we believe it useful to 
indicate the species most frequently encountered, or at least those 
most interesting from a medical point of view. 

Animal Parasites * 

The animal parasites are all invertebrates, which enter into the 
group of annelida and that of protozoa. 

Insects. — The parasite insects belong to the order of diptera or 
hemiptera. 

Diptera. — Among the diptera we shall simply note the flea, the 
chigoe, the oestrum, and the muscides. The larvae of certain insects 
may live beneath the skin or in the natural cavities of man. The best 
known of the skin larvae are the moyoquil worm of Mexico, the macaco 
worm of New Grenada, and the Cayor worm. The cavity larvae (Lu- 
cilia macellaria, Sarcophaga magnified, carnaria) develop in the 
sinuses of the face and may produce very grave disturbances. 

Hemiptera. — Hemiptera comprise the bedbug, and especially the 
louse, of which three varieties are admitted: the head louse (Pedicu- 
lus capitis) , the clothes louse (Pediculus vestimenti), and the crab 
louse (Phthirius pubis). The latter occasions, through a liquid which 
it secretes, the production upon the skin of slaty blue spots, peculiarly 
abundant when some intercurrent infection modifies the chemical con- 
stitution of the blood. Hence, these spots were first described in febrile 
diseases, and considered as an eruptive manifestation. 

* In preparing this chapter we have largely drawn from Dr. R. Blanchard's 
works on medical zoology. 

93 



94 INTRODUCTION TO THE STUDY OF MEDICINE 

It is very curious, from a point of view of general pathology, to 
note that these three species of lice live in determined regions, which 
they hardly ever leave. Evidently they find among the various parts 
of the body differences which we are unable to perceive. 

Acarina. — The principal species, from a medical point of view, is 
Sarcoptes scabiei, the agent of scabies or itch. 

This group comprises Ixodes — the Ixodes ricinus, which is quite 
innocent, and the Argas persicus, which produces, it is said, grave 
lesions. The Trombidium holosericum produces a larva of a beautiful 
red colour, known under the names red flea, harvest bug, or Leptus 
autumnalis, which fixes itself beneath the skin and gives rise to small 
papules attended by intense pruritus. Eecovery supervenes spon- 
taneously in six or seven days. The Demodex folliculorum is fre- 
quently observed in the sebaceous glands, mainly in the ala of the 
nose; it is believed to be the cause of acne punctata. 

The linguatulce, which are now looked upon as degraded acarina, 
are encountered in man in two states. As adults, they may invade the 
nasal f ossse ; in the larval state, they have been observed in the abdom- 
inal organs, and particularly in the liver. 

Helminthes. — The great group of helminthes, so important from a 
medical point of view, comprises a large number of species, parasites of 
man. We present in the following table those that are most common. 

Platyelminthes. 

Cestodes. 

Tceniadce. 

Taenia solium. 
" saginata. 
" echinococcus. 

Bothriocephalidm. 

Bothrioeephalus latus. 

Trematodes. 

Fasciolidce. 

Fasciola hepatica. 
Schistosomum haematobium. 

Nemathelminthes. 

Nematodes. 

AscaridcB. 

Ascarides lumbricoides. 
Oxyurus vermicularis. 

StrongylidcB. 

Eustrongylus visceralis. 
Uncinaria duodenalis. 



A2HMATE AGENTS 95 

TrichotrachelidcB. 

Trichocephalus trichiurus. 
Trichinella spiralis. 

FilaridcB. 

Filaria medinensis. 
" sanguinis. 

Angiostomidce. 

Strongyloides intestinalis. 

Taenia solium, Tcenia saginata, and Bothriocephalus latus repre- 
sent the three great tapeworms of man. The bothriocephalus is the 
least common; it is mostly met with in the regions of the lakes of 
Geneva and Neufchatel. In certain cases man is affected with ele- 
phantiasis, characterized by the development of numerous cysticerci 
occupying the subcutaneous cellular tissue, exceptionally the brain and 
the eyeball. As many as 2,000 tumours have been counted in one 
patient. 

Tcenia echinococcus is, when mature, a parasite of the dog, whose 
intestinal canal it inhabits. The eggs, swallowed by man, give birth 
to a hexacanth embryo, which penetrates into the organism, and, fixing 
itself in some organ or tissue, generally in the liver, produces a hydatid 
cyst. The latter grows, often reaching enormous proportions; but, 
although its contents include toxic substances, it acts chiefly in a 
mechanical manner, by compressing the neighbouring parts. 

Fasciola hepatica, distoma of the liver, inhabits the biliary pas- 
sages. It causes grave disturbances — pain, icterus, and a cachexia 
which finally ends in death. 

There exists a very grave disease, bilharziosis, which is chiefly ob- 
served in Egypt, and is due to Schist oma or Distoma haematobium, 
Bilharzia haimatobia. The parasite lives in the blood, on which it nour- 
ishes itself, but causes no disturbance; only it produces eggs pro- 
vided with spurs, which, stopping in the capillaries, tear them, and 
give rise to very grave hemorrhages. These sometimes occur as hema- 
turias (hematuria of Egypt), sometimes enterorrhagias. At the 
autopsy as many as 500 worms may be found in the portal system. 
The evolution is very long; it may persist for ten or fifteen years. 

Of the nematodes, Ascarides lumbricoides represent, as is known, 
worms extremely common. They are often found in great numbers 
in the intestine, as many as 5,000 in a case recorded by Fauconneau- 
Dufresne. Generally well borne, they may produce accidents of a reflex 
or even febrile nature, accompanied by grave general manifestations, 
described as typhoid lumbricosis. 

Oxyures are also very frequent. They are mostly met with in chil- 
dren, in the anus and the vulva, where they occasion intense itching. 



96 INTRODUCTION TO THE STUDY OF MEDICINE 

Eustrongylus visceralis is a very rare parasite, inhabiting the 
urinary passages, whence it may be voided with the urine. It produces 
grave disturbances, notably hematuria. 

On the contrary, Uncinaria duodenalis is very prevalent. It lives 
upon the intestinal mucous membrane, and there causes small hemor- 
rhages. The latter, by their repetition, soon give rise to a quite grave 
anaemic condition. To this worm is to be attributed the endemic 
anaemia which is observed in miners (anaemia of St. Gothard, of the 
coal mines of the Loire, in the north of France), and in those working 
in rice fields or in clay. 

We shall not dwell on the trichocephalus, which is frequently found 
in the digestive canal, where it is introduced through the drinking 
water. Generally inoffensive, it sometimes produces quite serious 
reflex phenomena. 

Otherwise important is Trichina spiralis, which produces the dis- 
ease known under the name trichinosis. Man is infected by eating 
insufficiently cooked pork. The parasites at first multiply in the 
intestine and produce diarrhoea and general disturbances resembling 
those of typhoid fever. Then they penetrate by the chyliferous ves- 
sels, invade the mesenteric glands, pass into the thoracic duct, reach 
the blood, and, after passing through the lung, arrive at the capil- 
laries ; others penetrate directly from the intestine into the blood, and 
yet others pass through the walls of the alimentary canal. The tri- 
chinae then become encysted in the muscles, and, in case they attack 
the respiratory muscles in great numbers, they bring about a fatal 
termination by asphyxia. While of very frequent occurrence in Ger- 
many, trichinosis is exceptional in France. 

The threadworm of Medina produces a disease called dracontiasis, 
characterized by the production of abscesses affecting particularly the 
legs and feet. When the abscesses are opened, one may see the para- 
site rolled up at the bottom of the wound. It may be extracted by 
drawing it out and coiling it around a small stick. The operation 
should be done with great care, for the rupture of the worm, probably 
giving issue to a toxic substance, is followed by very graVe disturbances. 

The name Filaria sanguinis is a collective term applied to diverse 
filariae living in the human blood. These parasites are encountered 
exclusively in hot countries. A great number of species are recognised, 
the four principal ones being Filaria nocturna or Bancrofts, Filaria 
diurna or loa, Filaria perstans, and Filaria Demarquayi. 

Filaria nocturna lives in the lymphatic vessels; it produces lym- 
phatic abscesses on the limbs, lymphatic tumours in the scrotum, and, 
according to Manson, elephantiasis of the Arabs. Filaria diurna 
lodges itself ordinarily between the conjunctiva and the eyeball. 



ANIMATE AGENTS 97 

Filaria perstans produces a peculiar affection, observed in negroes and 
described under the name " sleeping sickness." 

Strongyloides intestinalis is observed in patients suffering with the 
diarrhoea of Cochin China. 

Protozoa. — Very numerous parasites belonging to the group of pro- 
tozoa may be met with in man. 

We find, first, -among the infusoria, Balantidium coli, which is 
encountered in diarrhceal stools. This parasite has been seen about 
forty times, but it has never been encountered in France. 

Flagellata comprise three interesting species : Cystomonas urinaria, 
found in the urine ; Trichomonas vaginalis, which is very common, and 
has been met with in the vagina, the bladder, the alimentary canal, and 
in the expectorations of patients suffering with pulmonary gangrene; 
and Cercomonas or Lamblia intestinalis, which vegetates also in diar- 
rhoeal matter. 

We shall leave out of consideration for the present the other pro- 
tozoa, the coccidia, hemosporidia, and rhizopoda, since all that is 
important to know about them will be treated of in connection with 
infections. 

Vegetable Parasites 

Among vegetable parasites, we shall note, first, those concerned 
in the production of tinea. These are Trichophyton tonsurans, the 
agent of tinea tonsurans, herpes zoster, and parasitic sycosis, and 
Achorion Schoenleinii, the agent of favus. The study of these fungi 
has been pursued with great care in recent years, especially by Sabou- 
raud, Sabrazes, and Bodin, who have well shown the necessity of 
dividing them into a great number of species upon which we do not 
need to dwell here. 

Then comes the group of microsporon, comprising the Micro- 
sporon furfur, the cause of pityriasis versicolor; the Microsporon 
Audouini, to which alopecia is attributed; the Microsporon minutissi- 
mum, which is found in erythrasma; and the Microsporon anomceon, 
which produces pityriasis circinata. 

The other vegetables which we must now study may live under three 
different states. They are, according to circumstances, saprophytes, 
parasites, or infectious. We shall take them up when studying infec- 
tious agents. We shall only note them here. 

These vegetables are divided into two groups : Mycomycet^, com- 
paratively high fungi, and Phycomycet^e, which constitute a transi- 
tion between fungi and algae. 

Among Mycomycet^: we find aspergillus and eurotium, penicil- 
lium and blast omycetes, or yeasts. 



98 INTRODUCTION TO THE STUDY OF MEDICINE 

The Phycomycet^i include the important group of mucors. Mu- 
cor niger produces on the tongue a very tenacious black coating. The 
Mucors corymlifer, septatus, and ramosus enjoy with Aspergillus 
fumigatus and flavus and Eurotium repens and malignum the prop- 
erty of living as parasites. They are often met with in the auditory 
canal, where they give rise to the affections grouped under the general 
name otomycosis. 

Let us note also Cercosphcera Addisoni, which is found in various 
skin diseases and in certain alopecias. 

Finally, there have been described under the name leptomitus para- 
sites which are divided, according to the point of the organism where 
they were encountered, into leptomitus of the epidermis, of the urine, 
of the uterus, of the vagina, and of the aqueous humour. 

Infectious Agents 

Bacteria. — While bacteria are not the only parasites capable of 
producing infections, they incontestably hold the first place and repre- 
sent the true types of infectious agents. 

Their number is so considerable that we can not study all of them. 
We shall only note the principal species. 

According to the division which we have already admitted, we shall 
successively consider the micrococci and the bacilli, and in each group 
we shall study the common nonspecific and specific species. 

Nonspecific Micrococci. — The nonspecific micrococci are not very 
numerous. It suffices to know four of them: staphylococcus, strepto- 
coccus, pneumococcus, and tetragenus. 

Staphylococcus (Eosenbach, 1884), the most prevalent of all, is 
represented by small rounded elements, measuring from 0.7 micron 
to 1.2 micron, sometimes isolated, oftener united. They assume the 
form of diplococci when they are developed in a liquid medium. If 
we take a particle of a colony vegetating on some solid medium, we 
see that the grains form masses that have been compared, more or 
less exactly, to bunches of grapes. Hence the name given to this 
species. In many cases, however, the grains are in masses or in the 
form of long bands, sometimes even of small chains. 

This microbe develops readily upon the various media employed in 
bacteriology. On agar-agar, it forms a thick, moist growth; gelatine 
is rapidly liquefied, and the bottom of the tube contains colonies 
united in flocculent masses. Bouillon becomes uniformly turbid and 
often contains a mucous deposit. Milk coagulates in about eight 
days. Solidified serum liquefies slowly. 

The colour of the cultures varies notably according to circum- 
stances. Therefore three great varieties of staphylococci have been 



ANIMATE AGENTS 99 

admitted: Staphylococcus aureus, producing on agar-agar and pota- 
toes colonies of a superb orange-yellow colour; Staphylococcus citreus, 
whose name sufficiently indicates the colour; and Staphylococcus albus. 

It has long been a matter of discussion whether the three staphylo- 
cocci represent distinct species or but varieties of the same species. 
The latter opinion tends to prevail, since the different types are fre- 
quently found associated in the same morbid focus and numerous 
transitions are observed between well-differentiated samples. Finally, 
by certain experimental contrivances, we may easily cause the Staphy- 
lococcus aureus to lose its chromogenic power; it is thus transformed 
into the white variety. 

Staphylococci are found as saprophytes in soil, water, ice, air, 
dust, and various objects. They vegetate as parasites upon our in- 
teguments and mucous membranes, particularly upon the buccal 
mucous membrane, less frequently upon that of the intestine. They 
may penetrate into the excretory ducts of the glands ; even in the milk 
of healthy women, the white variety is almost constantly present. 

When they attain the rank of pathogenic agents, staphylococci, in 
most cases, give rise to suppurations. In general, it may be admitted 
that the chromogenic varieties are more virulent than the white vari- 
ety. According to the seat of the lesions and the activity of the germ, 
the effects vary greatly. In some cases, simple acneform pustules are 
observed; in others, boils or so-called carbuncle, or some affection 
peculiar to hot climates, the button of Biskra; elsewhere, it may as- 
sume the type of impetigo; at times, circumscribed or diffused phleg- 
mons, sometimes even gangrene. When the deeper structures are 
reached, suppurating foci will be observed either in the viscera or in the 
tissues. Osteomyelitis, for instance, is, in most cases, due to Staphy- 
lococcus aureus. In certain cases, instead of suppuration there is 
destruction of the affected parts (ulcerative endocarditis). In other 
cases, the infection becomes generalized ; a number of microbic centres 
are produced, ending in the formation of numerous small abscesses. 
This is the purulent infection or pyaemia. If the microbe is very 
virulent, no reactions are produced; the individual succumbs and the 
necropsy reveals no lesions. This is the process known as septicaemia. 

Streptococcus, observed by Coze and Feltz, by Pasteur and Do- 
leris, isolated from erysipelas by Fehleisen (1883) and from suppu- 
rations by Eosenbach (1884), is a micrococcus measuring from 0.3 to 
1 micron. They have the very characteristic property of grouping 
themselves into more or less long chains. Some chains are made 
up of 3 or 4 elements, others of 30 to 40, and present then the 
form of a rosary or pearl necklace. In certain cases, diplococci 
only are found; in others, the streptococci overlap each other and 
LofC. 



100 INTRODUCTION TO THE STUDY OF MEDICINE 

agglomerate so as to form colonies which, on superficial examination, 
appear to be staphylococci. In general, all the elements of the same 
chain are of equal size; in certain cases, a few are more voluminous 
and break the uniform contour which is usually observed. 

This microbe, a facultative anaerobe, produces on agar-agar small, 
slightly elevated, almost translucent, rounded colonies ; the appearance 
is similar on gelatine, which is not liquefied. Bouillon is at first uni- 
formly turbid, but soon becomes clear; the microbes fall to the bottom 
of the tube, where they collect into small granules or even small 
masses, which are readily scattered when the liquid is agitated. 

The streptococcus develops readily on potatoes, but, as a rule, does 
not produce colonies visible to the naked eye. 

Its action on milk is inconstant; in most cases this medium is 
coagulated by it. 

The most luxuriant cultures are obtained in serum or in the liquid 
of ascites, either pure or mixed with bouillon ; it is also in this medium 
that the microbe attains its maximum degree of virulence. 

Like the staphylococcus, the streptococcus is widely distributed. 
It is found in the air, in water, and in the soil; it readily invades 
putrescible matters, and is frequently met with upon the skin, in the 
buccal cavity, where it is constant, and at times in the intestinal canal, 
where it inhabits mainly the duodenum. 

This microbe may produce four orders of morbid manifestations: 
oedema, suppuration, pseudo-membranes, and gangrene. 

Erysipelas is an inflammatory oedema par excellence; at times the 
dermatitis terminates at some points in the formation of small ab- 
scesses. This fact has been made use of to prove the identity of the 
streptococci of erysipelas and of suppuration. 

Between exudative and suppurative inflammations we find lym- 
phangitis, which occupies a position intermediate between erysipelas 
and phlegmon. Among the suppurative lesions we must mention the 
adeno-phlegmons, and particularly the diffuse phlegmons, which 
are nearly always due to streptococcus. When it is localized in the 
viscera, streptococcus still gives rise to the same lesions — e. g., in the 
kidney it produces an acute nephritis; in the lung, broncho-pneu- 
monias ; while in the other organs or in the serous membranes it causes 
more or less extended suppurations. If it attacks the inner coat of the 
circulatory system, it causes arteritis, phlebitis, and endocarditis, espe- 
cially ulcerative endocarditis. 

Finally, becoming generalized, it may, like the staphylococcus, per- 
haps oftener than the latter, produce pyaemia or septicaemia. Puer- 
peral septicaemia is nearly always dependent upon the streptococcus. 

The part played by the streptococcus in the formation of false 



ANIMATE AGENTS 101 

membranes has been well established by numerous observations of 
diphtheroid sore throats, in which this microbe is met with predomi- 
nantly or almost exclusively. The same is true of other parts of the 
organism, notably of the vulva and vagina, which may in cases of 
puerperal infection become covered with false membranes caused by 
streptococcus. 

Lastly, streptococcus may produce gangrene. This is observed in 
the patches of erysipelas, as well as in gangrene of the extremities con- 
secutive to acute arteritis; the same microbe, it seems, may of itself 
provoke pulmonary gangrene, without the intervention of other germs. 

Many authorities have admitted a great number of varieties or 
species of streptococci. The present tendency is to draw closer to- 
gether and to unite the different species. It should not be forgotten, 
however, that different species are distinguished from each other by 
certain biological properties. It is well demonstrated, for example, 
that the serum of animals immunized against one variety of strepto- 
coccus often exerts no influence upon other varieties. Without con- 
cluding from this fact that there are specific differences, we must, 
nevertheless, admit that there are modifications sufficiently distinct to 
be expressed by peculiar biological characteristics. 

The third micrococcus that we must mention is the Pneumo- 
coccus. It was discovered in pneumonia by Talamon, thoroughly 
studied by Fraenkel, who identified it with the microbe of sputum 
septicaemia of Pasteur, Vulpian, and Sternberg, and subsequently by 
Weichselbaum. The pneumococcus is designated in France under the 
name of Talamon-Fraenkel, in Germany as Diplococcus pneumonia 
(Fraenkel), and in Austria as the Fraenkel- Weichselbaum diplococcus. 
It has been called by Gamaleia Streptococcus Pasteuri. 

This microbe presents itself under the form of small lanceolate 
granules, comparable to the grains of barley, measuring from 1 to 1.5 
micron. It is sometimes isolated, oftener united in pairs or in short 
chains, comparable to those of streptococcus (Streptococcus pneu- 
monice). The individual cocci are remarkable for the clear capsule 
that surrounds them. This capsule is especially apparent when the 
microbe is developed in a medium rich in albumin — viz., in the living 
organism and in the blood serum. 

More delicate than the preceding species, the pneumococcus does 
not develop at ordinary temperature; its development begins at about 
24° C. On solid media, such as agar-agar or gelatinized serum, it 
gives rise to minute colonies resembling dewdrops, scarcely visible to 
the naked eye. Gelatine is not liquefied. In bouillon extremely small 
granules are observed. The best media are represented by blood serum, 
and particularly defibrinated blood, coagulated by heat. On the latter 



102 INTRODUCTION TO THE STUDY OF MEDICINE 

medium, proposed by Gilbert and Founder, the microbe develops lux- 
uriantly and decolourizes the colouring matter of the blood, which is 
changed from brown to yellowish white. This phenomenon appears to 
be characteristic. 

The pneumococcus, though somewhat less widely distributed than 
the preceding microbes, has been encountered in the air and in dust, 
but it is a parasite rather than a saprophyte; 20 out of 100 healthy 
individuals harbour it in their saliva. It may also be found in the 
nasal mucus and even in the intestine. 

First encountered in fibrinous pneumonia, pneumococcus may pro- 
duce, even in the respiratory apparatus, very diverse affections — bron- 
cho-pneumonias and bronchites. It frequently induces suppuration 
in the serous membranes : meningitis, pericarditis, pleurisy, perito- 
nitis, which are characterized by the presence of thick, greenish, semi- 
solid exudations, extremely rich in fibrin. It may also produce 
arthritis, otitis, parotiditis, and localize itself upon the endocardium 
and cause vegetative or ulcerative endocarditis. Less frequently it 
invades the whole organism and induces septicaemia. 

Very closely related to, if not identical with, the pneumococcus is 
Micrococcus intracellular is meningitidis, which is the cause of cerebro- 
spinal meningitis. 

Of late, attention has been drawn to Tetragenus (Micrococcus 
tetragenus, Gaffky, 1883). Morphologically, it is made up of 4 micro- 
cocci, united on the same plane and often surrounded by a capsule. It 
produces, in various media, moist, white colonies (a yellow variety 
also has been described). It does not liquefy gelatine; forms in bou- 
illon a thick deposit. 

This microbe is frequently met with in the mouth. It takes a 
prominent part in the development of " sore throats," in which, by 
cultivation on agar-agar, it is found in three fourths of the cases. 
From the buccal cavity, tetragenus may invade the neighbouring parts : 
in this way it causes dental abscesses and adeno-phlegmons of the 
cervical region ; making its way into the ear, it produces otitis or mas- 
toiditis. At other times, carried toward the respiratory apparatus, it 
produces a purulent bronchitis a pulmonary abscess, or contributes to 
the formation of tubercular cavities. Its presence has also been proved 
in cases of septicaemia and pygemia, as well as in the urine of patients 
suffering with scarlatinal nephritis. 

Nonspecific Bacilli. — At the head of the least of nonspecific ba- 
cilli is placed the Colon Bacillus (Bacillus coli communis, Bac- 
terium coli commune), discovered by Escherich. Very variable in its 
morphology, the colon bacillus presents itself sometimes under the 
form of small, motile rods measuring from 2 to 4 microns; some- 



ANIMATE AGENTS 103 

times under that of oval elements, which might easily be mistaken for 
micrococci, and at times under the form of quite long filaments. It is 
a facultative anaerobic motile bacillus, provided with from 4 to 10 
vibratile ciliae. It develops readily between 15° and 46° C. in all the 
media employed in bacteriology. On agar-agar or serum it forms a 
whitish layer ; on gelatine, ovoid, transparent, or opaque colonies, which 
do not liquefy the medium. Potato is covered with a thick brown 
coating, and artichoke assumes a beautiful greenish tinge. Milk, in 
consequence of the fermentation of the lactose, becomes acid and coag- 
ulates more or less rapidly. Bouillon becomes uniformly turbid, and 
quite often contains little flocculi; in peptonized bouillon notable 
quantities of indol are formed. 

On the various media the cultures emit a disagreeable odour, some- 
times recalling that arising from decomposed urine, sometimes that 
of putrefaction. 

Gas is sometimes abundantly produced in milk, potatoes, and gela- 
tine. It is then due to a variety long considered to be a particular 
species — namely, Bacillus lactis aerogenes. 

Certain varieties of colon bacilli do not ferment lactose or produce 
indol; these are called paracolon bacilli. Experimenters have several 
times succeeded in inducing, by serial cultures in milk, the fermenta- 
tive power, which was previously lacking. 

The colon bacillus is a very prevalent microbe, perhaps the most 
widely distributed of all. It is found in the air, soil, and water, and 
it is constantly met with in the alimentary canal of man and of ani- 
mals, in the mouth, in the stomach, and particularly in the intestine. 
Discharged with the fseeal matter, it readily soils the external genitals, 
where its presence is also almost constant. In certain animals it 
affects .the mammary glands, as is notably the case with the cow; 
hence, the colon bacillus is encountered in the milk, where Pasteur 
described it under the name lactic ferment. 

When this microbe attains virulence, it produces very various 
lesions. It is the principal agent of intestinal infections — e. g., acute 
or chronic enteritis, infantile cholera, cholera nostras, colitis, and 
appendicitis very frequently depend upon it. In cases of dysentery of 
hot countries, and at times in dysentery nostras, the stools contain 
in great abundance a variety of colon bacillus which has been consid- 
ered the cause of the disease. From the intestine the microbe may 
make its way to the excretory ducts, and produce suppuration in the 
biliary passages or inflammation in the pancreas; or else, passing 
through the walls of the intestine, it gives rise to peritonitis ; or, again, 
passing by the portal vein, it localizes itself in the liver, and there in- 
duces infections, degenerations, and often grave icterus. 



104 INTRODUCTION TO THE STUDY OF MEDICINE 

Less frequently it acts in the month, produces sore throat, or 
reaches the neighbouring parts, notably the parotids. 

While it assumes a very important role in intestinal pathology, its 
etiological significance in urinary pathology is by no means inconsid- 
erable. It produces cystitis, and may spread from the bladder toward 
the kidney, where it frequently induces lesions terminating in renal 
insufficiency. It is the great agent of death in patients suffering from 
urinary disorders. 

Lastly, in women, it has several times produced a variety of puer- 
peral septicaemia. 

It must be remembered that, in order to affirm that a certain lesion 
is due to the colon bacillus, it does not suffice to prove its presence in 
the cadaver. After death, or rather during the agony, the colon bacil- 
lus often leaves the alimentary canal, particularly in those cases where 
the intestine has suffered alteration or ulceration, and invades the 
other organs, especially the liver. 

It has not always been possible to refer to the colon bacillus group 
the microbes encountered in the various lesions above mentioned. 
Therefore authors have described as distinct species a whole series of 
agents, which are at present identified. Besides the Bacillus lactis 
aerogenes and the lactic ferment, which we have already noted, we must 
class with the group of colon bacilli Bacillus neopolitanus, found by 
Emmerich in the organs of cholera subjects, Bacillus pyogenes faztidus 
of Passet, the septic bacterium (Clado), and the pyogenic bacterium 
(Albarran and Halle) of urinary infections, the bacillus of dysentery 
of Chantemesse and Widal, the bacillus of ulcerative endocarditis of 
Gilbert and Lion, etc. 

We may also class this microbe with the bacillus of psittacosis, 
described by Nocard, Gilbert, and Fournier. This is a microbe very 
common among parrots, and produces in man extremely grave broncho- 
pneumonia. 

Some authors consider as a variety of colon bacillus the pneumo- 
bacillus of Friedlander, which should not be confounded with the 
pneumococcus. It differs from the colon bacillus by the presence of a 
capsule, which, however, is not constant. It produces in man sore 
throat, broncho-pneumonia, and septicaemia. 

Another septicaemic agent, Bacillus septicus putidus, encountered 
for the first time in a patient dead of septicaemia consecutive to 
cholera, deserves to be placed close to colon bacillus. It clearly differs 
from the latter by a very important characteristic : it liquefies gelatine. 
Pathogenic for animals, it has served for various experimental inves- 
tigations. 

Three other nonspecific bacteria may be met with, which are of 



ANIMATE AGENTS 105 

great importance in experimental and comparative pathology. These 
are the bacillus of hemorrhagic septicemia, Proteus vulgaris, and Ba- 
cillus pyocyaneus. The latter, discovered by Gessard in 1882 and well 
studied by Charrin, possesses the interesting property of engendering 
a blue colouring matter, pyocyanin, which may be obtained in a crystal- 
line state. 

Leptothrix. — In the group of leptothrix we shall only mention 
Leptothrix buccalis, which may produce in man anginas (pharyngo- 
mycoses) of a particular character, abscesses, and even invade the 
economy. 

The characteristic common to the various bacteria thus far noted 
lies in the fact that all produce analogous inflammatory processes. 
The dominant feature, from a clinical point of view, is the localiza- 
tion. The evolution of the morbid phenomena, their innocence or 
gravity, is dependent upon the tissue or organ attacked and upon 
the extent of the parts involved. Finally, these same agents may 
invade the economy, causing septicaemia or pyaemia, according as in- 
flammatory reactions are present or absent. 

Specific Micrococci. — The specific bacteria comprise but two 
micrococci. 

The best known is the microbe of gonorrhoea, the Gonococcus, dis- 
covered by Neisser in 1879. The appearance of this coccus is quite 
characteristic. In examining the pus of gonorrhoea, we find the gono- 
cocci made up of two segments coupled, presenting somewhat the form 
of two beans, arranged with their concave surfaces toward each other. 
These microbes lie free or are inclosed within pus cells or epithelial 
cells; in most cases the same cell incloses a great number of them. 
They are not stained by Gram's method, and this fact serves to dif- 
ferentiate them from the common pus cocci. 

The cultivation of gonococcus is a matter of difficulty. For a long 
time human blood serum was used as a medium. At present it is 
known that this coccus may develop in the serum of the rabbit ; upon 
glycerine agar-agar, where it forms white, thin, transparent colonies; 
or on potatoes, where it produces minute drops. 

This microbe causes a specific suppuration in the urethra, in the 
vagina, and at times in the rectum, the nose, and the conjunctiva. 
It is the usual causative agent in purulent ophthalmia of the newborn. 

In cases of urethral or vaginal gonorrhoea, the gonococcus mani- 
fests hardly any tendency to leave the genital mucous membranes. 
Even though it locates itself with great tenacity in the cells and the 
glandular crypts, it only exceptionally invades the neighbouring 
glands, and but rarely enters the blood. The complications of gonor- 
rhoea, the arthropathies, are due to secondary infections. In most cases 



106 INTRODUCTION TO THE STUDY OF MEDICINE 

the gonococcus simply opens the way to the common pyogenic bacteria. 
The rheumatism of gonorrhoea must be considered as an attenuated 
pyaemia. Gonococcal arthropathies do exist, but they appear to be 
rare, although they are more frequent than was formerly believed. 

The second specific micrococcus has been little studied; it is the 
Microbe of Mumps, described by Laveran and Catrin. 

The Specific Bacilli. — The specific bacilli are more numerous. 
There are thirteen of them, of which ten are aerobic and three ana- 
erobic. 

The specific aerobic bacilli are headed by the Bacillus Anthracis 
(bacteridie cliarbonneuse) , discovered by Davaine in 1850. The latter 
is found in the blood of animals which have succumbed to the disease. 
It appears in the form of small nonmotile rods, measuring from 5 to 6 
microns in length and 1 to 1.5 micron in breadth; the rods are some- 
times surrounded with a capsule, and the ends are cut at right angles 
and slightly sinuous. In artificial media, particularly in liquid media, 
these rods become elongated in the form of segmented filaments, often 
very long, which soon produce spores. Spores are never found in the 
animal organism or in cultures grown in blood serum. 

Bacillus anthracis readily develops in the presence of oxygen. It 
grows between 10° and 45° C. On agar-agar it gives rise to white 
colonies, on gelatine to granular colonies, which rapidly liquefy the 
medium and form a deposit analogous to a mass of rolled thread. 
Potatoes becomes covered with a thick coating. Bouillon, at first 
turbid, later becomes clear, the microbes falling to the bottom of the 
tube in the form of dense white flocculi. 

The action on milk is quite variable. If the milk is put in a tube, 
the bacillus, living only in the upper layers, secretes a casease, which is 
diffused and produces coagulation. If, on the contrary, aeration is 
ample — viz., if the milk is put in a large vessel, at the bottom of which 
it forms a thin layer — the casein is digested and transformed into pep- 
tone as fast as it is coagulated; the milk assumes the character of a 
thick and brownish liquid. 

Owing to the nature of its spores, Bacillus anthracis easily resists 
destruction. It persists for a very great length of time in the soil and 
water, thus causing very deadily epidemics and epizooties. 

We must recognise, however, that in most cases contamination 
takes places otherwise. Man is most often affected in dealing with 
the cadavers of anthrax animals, or by manipulating the products 
derived from them — wool, horns, skin, etc. 

Another bacillus, which also plays a part in man and animals, is 
the Bacillus of Glanders, Bacillus mallei, well described by Loeffler 
and Schutz in 1883. 



ANIMATE AGENTS 107 

This organism occurs in the form of long, slender, motile rods, 
measuring from 2 to 5 microns, often inclosing in their interior feebly 
coloured vacuoles. They grow very readily on agar-agar with glycer- 
ine; in bouillon, in which they form a viscous precipitate, and on pota- 
toes, on which they produce a thick coating of a greenish-blue colour, 
the appearance of which is almost characteristic. 

The disease generally attacks the horse, which transmits it to man. 
The feeble resistance of the microbe explains why direct contagion is 
observed as a rule. 

The Typhoid Bacillus, described by Eberth in 1880, presents 
itself in the form of cylindrical rods, measuring 0.6 to 1 by 2 to 4 
microns. In old cultures it produces filaments and forms of invo- 
lution. 

In many respects this microbe resembles the colon bacillus. It 
differs from it in certain important characters. It is more motile, 
this being due to the fact that it is provided with a greater number of 
cilise, 8 to 24. Colonies on agar-agar and gelatine are more trans- 
parent; on potatoes they are hardly visible, or form a light, whitish 
coating. Contrary to the colon bacillus, the typhoid bacillus does not 
yield a green colour when cultivated on slices of artichoke. It produces 
no indol in peptonized bouillon, does not ferment lactose, or coagulate 
milk. It resists much less the action of antiseptics — carbolic or arseni- 
ous acid. 

However, these characteristics have not an absolute value; in the 
group of paracolon bacilli are found numerous species which seem 
to establish an insensible transition between the bacillus of Eberth 
and that of Escherich. 

A final characteristic, derived from serum reaction, has lately been 
spoken of. It has been noted that the serum of animals immunized 
against the typhoid bacillus, or that of individuals attacked by typhoid 
fever, agglutinates the typhoid bacillus, but never the colon bacillus. 
This fact, although disputed, is interesting ; but it is not of such great 
value as might be supposed, for similar reactions are observed with 
varieties of one and the same species. This is what occurs notably with 
the cholera vibrios. 

It is then conceivable that several authorities persist in believing 
that the typhoid bacillus is but a variety of the colon bacillus. This 
theory, enunciated and sustained by Eodet and G. Koux, has appeared 
very seductive, for it explains the cases in which typhoid fever is gen- 
erated spontaneously — that is, without any contagion. However, the 
idea of the specificity of the t3^phoid bacillus has just found a new 
argument in the researches of Eeumlinger and Schneider. These 
authors have proved that the typhoid bacillus is met with in the intes- 



108 INTRODUCTION TO THE STUDY OF MEDICINE 

tines of normal individuals. It might then bring about the disease 
on the occasion of debilitating causes, and notably of overwork. Thus 
excited, it produces a case which is apparently spontaneously devel- 
oped, and it becomes the starting point of an epidemic which is propa- 
gated through contagion. 

Infection takes place mostly through the agency of water, excep- 
tionally through the soil or the air. 

The aqueous origin of typhoid fever is no longer questionable. 
Numerous observations have established that the disease undergoes 
recrudescence when the drinking waters are polluted, and diminishes 
when hygienic measures are enforced. The precautions taken in recent 
years against unhealthful water are therefore praiseworthy; but if 
observations are very conclusive, experiments are much less so. The 
difficulty of distinguishing the typhoid bacillus from the colon bacillus 
does not enable one to admit the majority of analyses in which the 
typhoid bacillus is said to have been found in the water. The colon 
bacillus exists in all waters, and thus renders researches very difficult. 
This is what resulted from an experiment of Grimbert: This author 
introduced into 1,000 cubic centimetres of water 1 cubic centimetre 
of a culture of the colon bacillus and 1 cubic centimetre of a typhoid 
culture. He agitated the mixture and showed that it is impossible to 
recover the typhoid bacillus or to isolate and differentiate it from the 
colon bacillus. 

The Bacillus of Diphtheria, observed by Klebs in 1883, and 
fully described by Loeffler in 1884, is a nonmotile rod, straight or 
rounded, measuring 0.7 by 2.5 to 3.5 microns. The elements are iso- 
lated or united in couplets, often well aligned, and, as is said, placed 
in range of battle. In old cultures we frequently meet with involution 
forms presenting the contour of clubs or spindles. 

The diphtheritic bacillus develops at a temperature of about 24° 
C. ; its growth is arrested at 42° C. and is particularly luxuriant 
between 35° and 37° C. On agar-agar quite distinct colonies or gray- 
ish streaks are seen ; on gelatine, small spherical colonies ; in bouillon, 
masses that fall to the bottom of the culture tube. The bacillus does 
not develop on potatoes. The most characteristic cultures are ob- 
tained by inoculation upon gelatinized blood serum. At the end of 
twelve hours the nutrient medium, maintained at 38° C, is covered 
with small white or gray colonies, about the size of a pin's head. It 
is, as is known, by means of cultures on serum that one can readily 
establish the bacteriological diagnosis of diphtheria. 

This microbe may be encountered as a saprophyte, a parasite, or a 
pathogenic agent. As a saprophyte, it may live in dung and rags; 
as a parasite, it vegetates in the buccal cavity of healthy individuals; 



ANIMATE AGENTS 109 

as a pathogenic agent, it produces pseudo-membranous lesions, occu- 
pying generally the throat, invading the larynx and the nasal cavities, 
less frequently the conjunctiva, and exceptionally the bronchi. It may 
also attack other mucous membranes exposed to the air, notably the 
genital mucous membrane or the skin. 

Eapidly destroyed by the rays of the sun, the diphtheria bacillus 
retains its vitality for a very great length of time when sheltered from 
light. There are cases on record in which the clothing of a child dead 
with diphtheria was packed in a drawer, and when, a year or two later, 
it was taken out, caused the infection to reappear. 

The Bacillus of Influenza or Grippe, discovered by Pfeiffer in 
1890, is one of the smallest that is known; it is a nonmotile, recti- 
lineal rod, 0.5 micron long, separate or in chains of three or four 
elements. It develops upon agar-agar covered with a layer of the 
blood of man or of the pigeon, in the form of small, homogeneous 
colonies, visible only under a magnifying glass. The growth is some- 
what more abundant on glycerine agar-agar; in bouillon with blood 
it assumes the form of small flocculi. 

We now come to one of the most important microbes — namely, the 
Tubercle Bacillus — discovered by Koch in 1882. This bacillus oc- 
curs in the form of nonmotile rods, from 2 to 4 microns in length. 
The bacilli possess a tinctorial reaction altogether characteristic. They 
are penetrated with great difficulty by the aniline colours. One must 
employ energetic mordants and leave the microbes in the colouring 
bath during twenty-four hours, or else heat the liquid until it gives off 
vapours; the staining is then produced within a few minutes. Once 
stained, the microbes retain the dye tenaciously, resisting the action 
of nitric acid in the proportion of one third, which decolourizes the 
other bacteria. They appear alone in preparations thus treated. 

The tubercle bacillus readily develops in blood serum, in bou- 
illon and agar-agar mixed with glycerine or various sugars, and on 
potatoes with glycerine. On solid media it forms dry or slightly 
moist scales ; on liquid media, scaly, wrinkled films or pellicles, which, 
at the end of a certain time, fall to the bottom of the culture tube. 

Eecent researches demonstrate that in certain conditions the 
tubercle bacillus undergoes remarkable morphological modifications. 
Projections and ramifications appear, which at times terminate in 
club-shaped swellings. The microbe is therefore much more highly 
organized than was at first believed. But no conclusion has as yet 
been reached as to its proper position in botanical classification. 
Some authors, considering the lateral buddings as true ramifications, 
place it in the group of streptothrix, by the side of actinomyces. Oth- 
ers, arguing that the ramifications are false, class it among the bac- 



HO INTRODUCTION TO THE STUDY OF MEDICINE 

teria, in the group of cladothrix. It is at times considered to be 
referable to a somewhat special kind, that of crenothrix. To conform 
to usage, we have left the agent of tuberculosis among the bacteria. 
If it finally be ranked with streptothrix, this would be the best argu- 
ment against those who still maintain that all infectious diseases are 
of bacterial origin. 

The tubercle bacillus is remarkable for its high pathogenic power. 
It attacks equally man, mammalia, birds, and even cold-blooded ani- 
mals — the ophidia and fish. As in the case of many other microbes, 
there exist several varieties of tubercle bacilli. Three principal vari- 
eties have been described: (1) The bacillus of human tuberculosis, 
which is met with in man, mammalia, and, among the birds, in par- 
rots; (2) the bacillus of avian tuberculosis, which attacks particu- 
larly the gallinae; (3) the bacillus of fish tuberculosis. Struck with 
these differences, some authors claimed to see in these three agents 
three distinct species. At the present day all have agreed to consider 
them simply as varieties that may be transformed one into the other. 

The tubercle bacillus is endowed with a very great vitality and 
easily resists causes of destruction. This fact alone explains its great 
prevalence. None of the mammalia are entirely immune to it. It is 
the veritable scourge of our epoch. In Paris tuberculosis is respon- 
sible for 4.9 deaths out of each 1,000 inhabitants; in cities with less 
than 5,000 souls the figure is 1.81. Among animals, the bovine species 
are the most frequently attacked. Contrary to popular opinion, tuber- 
culosis is of very frequent occurrence in the domestic carnivora, nota- 
bly in the dog (Cadiot). 

Tuberculosis may be transmitted from animals to man. More fre- 
quently infection takes place from man to man, and may give rise to 
true epidemic centres. In the majority of cases inoculation occurs in 
the respiratory passages; it is through the sputa that the bacilli are 
transmitted. They represent a real social danger against which a 
struggle has justly been inaugurated in recent years. 

The other pathogenic bacilli are less important for our studies; 
they require but brief mention. 

First is the Bacillus of Leprosy, discovered by Hansen, whose 
morphological and tinctorial characteristics are quite analogous to 
those of Koch's tubercle bacillus. 

Let us mention the Bacillus of Plague, recently discovered by 
Yersin and Kitasato; a bacillus analogous to the colon bacillus, de- 
scribed by Sanarelli, under the name Bacillus icteroides, as the agent 
of Yellow Fever; and a bacillus encountered by Roger and isolated 
by Lemoine and by Barbier and Tollemer from the stools of patients 
suffering from Dysenteriform Enteritis. The latter bacillus is 



ANIMATE AGENTS 111 

very virulent; it can in certain cases give rise, in animals under ex- 
periment, to intestinal ulcerations analogous to those of dysentery and 
to hepatic abscesses. Lastly, the Bacillus of Soft Chancre (Du- 
crey, 1889), a thick and short bacillus, often constricted in the middle, 
sometimes arranged in the form of chains, which no one has succeeded 
in cultivating. 

Among the microbes thus far studied, several are facultative ana- 
erobics. We have yet to mention three which vegetate only when ex- 
cluded from air. These are the bacilli of tetanus, of gaseous gan- 
grene, and of rheumatism. 

The Bacillus of Tetanus or Bacillus of Nicolaier (1884) is 
represented by very slender elements, from 2 to 5 microns long, motile, 
and generally provided with a large terminal spore, which gives them 
the appearance of pins. Sown on agar-agar and protected from air, 
they produce flocculent colonies and cause a liberation of gas, which 
splits the medium. Gelatine is rapidly liquefied and filled with gas 
bubbles. Bouillon is at first made turbid, but subsequently becomes 
clear, the microbes falling to the bottom of the tube, where they form 
a granular deposit. The culture has a very strong and disagreeable 
odour. 

Owing to its spores, the tetanus bacillus is very resistant and very 
widely distributed. It is found in the soil, in mud, in dung, and dust ; 
it is also met with in the digestive canal of herbivora, and is passed 
in abundance in their excreta. When it assumes pathogenic properties 
it develops at the point of infection, where it remains, and causes an 
intoxication of the organism by the substances which it secretes. 

There have been observed in man and in horses epidemics and 
epizooties of tetanus, which are explained by the transportation of the 
germs through badly disinfected instruments. 

The second anaerobic microbe was discovered by Pasteur, who de- 
scribed it, in 1885, under the name of septic vibrio. This quite 
improper designation has give rise to an error which has found expres- 
sion in certain didactic articles. It has been stated that this microbe 
is the cause of septicaemias, in opposition to staphylococcus, which is 
generally believed to be the causative agent in pyaemias. The designa- 
tion of this microbe as the bacillus of gangrenous septicaemia, a term 
adopted by the school of Lyons, is not any better. The name bacillus 
of malignant oedema, used in Germany, can not be accepted, for in 
France one of the clinical forms of anthrax is thus designated. It is 
therefore better to abandon all these terms and to adopt the name 
Bacillus of Gaseous Gangrene, which has trie advantage of avoid- 
ing all confusion and of immediately recalling the nature and appear- 
ance of the lesions. 



112 INTRODUCTION TO THE STUDY OF MEDICINE 

This bacillus presents itself at times under the form of small 
motile rods, isolated or in couplets, measuring from 3 to 5 microns 
and often including a terminal or median spore; at other times under 
the form of filaments measuring from 15 to 40 microns and never con- 
taining any spores. 

Sown on agar-agar, the bacillus of gaseous gangrene produces a 
cloudy colony with arborization; it liquefies gelatine and blood serum 
by evolving gas; bouillon is at first turbid, but subsequently becomes 
clear and full of gas bubbles. 

Like the tetanus bacillus, with which it is frequently associated, 
the bacillus of gaseous gangrene is very widely distributed. It is 
almost constantly present in the soil, in dung, in the mud of waters ; 
and it is often met with in the alimentary canal of man and animals. 

It is a very resistant microbe. Introduced into a wound, it pro- 
duces a large focus of gangrene with evolution of gas which infiltrates 
the surrounding tissue. The lesion manifests a great tendency to 
extension, and death supervenes through intoxication. This microbe, 
like that of tetanus, remains localized at the point of introduction, 
and acts through the medium of the toxines which it produces. 

Very closely related to, if not identical with, this bacillus is the 
bacillus of symptomatic anthrax. The morphological characters and 
the appearance of the cultures are similar. The differences lie in their 
pathogenic action. This microbe attacks cattle, in which it produces a 
disease called symptomatic or emphysematous or bacterial anthrax. 
It is of no importance in human pathology, but has acquired great 
interest because of the numerous researches in general pathology for 
which it has served. It ma}' not be useless to add that there exists no 
relation whatever between symptomatic anthrax and the ordinary or 
bacterial anthrax. 

We have yet to mention among the anaerobics the bacillus of 
Acute Articular Eheumatism. Achalme and Thiroloix have found 
in the blood of rheumatic patients an anaerobic bacillus which, by its 
morphological characteristics, is allied to the anthrax bacterium. Tri- 
boulet and Coyon have also found a bacillus, but differing from the 
preceding. These observations are too recent to permit an opinion as 
to the part played by these microbes. 

Spirilla. — Two spirilla must be studied. The first known is the 
Spirillum of Eecurrent Fever, discovered by Obermeier in 1873. 
It presents itself under the form of very motile elements, having 15 to 
20 spiral turns and measuring from 15 to 50 microns. It is seen 
during the paroxysms in the blood of the patient, or of the monkey 
experimentally inoculated. This parasite has not yet been success- 
fully cultivated. 



ANIMATE AGENTS 113 

The microbe of Cholera, called also spirillum of cholera, cholera 
vibrio, and comma bacillus, was isolated and cultivated by Koch in 
1884. It occurs in the form of a half parenthesis, of an S, or of the 
Greek character <o ; at times, however, certain individuals are recti- 
lineal or drawn out into filaments. In old cultures spherical involu- 
tion forms are found. This microbe is motile, owing to the presence of 
numerous cilia. 

It develops readily in various culture media; in gelatine it pro- 
duces small colonies; inoculated by stab culture in a tube, it pro- 
duces a spherical excavation terminating in a rectilineal prolonga- 
tion. This appearance is almost characteristic. The microbe liquefies 
coagulated serum with equal rapidity. Upon agar-agar it forms a 
white and thick layer; on potatoes, a brown layer. Bouillon becomes 
turbid and covered with a thin pellicle. Milk does not coagulate. 

The development is very readily effected in peptonized water. This 
medium, which is often employed for its bacterial diagnosis, is charged 
with a great quantity of indol; treated with nitric acid, the liquid of 
the culture assumes a violet-red colour. This is the reaction called 
" Cholera-roth." 

The cholera bacillus lives as a saprophyte in water, and as a para- 
site in the alimentary canal of healthy human individuals. When it 
becomes excited, it multiplies within the intestinal cavity, which it 
manifests no tendency to leave; the lesions which it provokes must be 
attributed to the absorption of toxines to which it gives rise. 

Phycomyces. — Close to those bacteria capable of producing infec- 
tious diseases is reserved an important place for the parasites of a 
higher order. 

The latter are headed by a group of streptothrix, also called 
Oospora or Nocardia. The most important of this kind is the Strepto- 
thrix bovis or actinomyces, which produces in man and in animals a dis- 
ease described under the name Actinomycosis. Observed in the bovine 
species by Eivolta (1868 and 1875), who looked upon them simply as 
crystals, actinomycetes have been better studied by Perroncito, Bol- 
linger, and particularly by Harz and Israel, who proposed the term 
now adopted to recall their vegetable nature and their radiate form 
SlktU), tVos = rays, /jlvktjs = fungus ) . The first cases observed in man 
were published by Israel (1878) and Ponfick (1879-1882). 

Actinomyces gives rise to two kinds of lesions : to productions of 
sarcomatous appearance and to suppurative foci. In both cases yel- 
low granules have been found, resembling sulphur flowers. The para- 
site is readily seen on microscopical examination of one of the gran- 
ules. It is essentially formed in the following manner: a central 
part, made up of a felting of mycelial filaments, which irradiate like 



114: INTRODUCTION TO THE STUDY OP MEDICINE 

the spokes of a wheel and terminate in swellings of a club-shaped form 
or elongated in a pyriform manner. 

This vegetable, a facultative anaerobic, may be cultivated, although 
with difficulty, in various media, such as solidified serum, glycerine 
agar-agar, milk, bouillon, and vegetable infusions. 

It lives as a saprophyte upon vegetables, and especially upon the 
graminaceae. The herbivora are infected by grazing on the plants. 
The disease is particularly frequent in cattle, but it is also observed in 
swine, sheep, dogs, and the horse, although in the latter animal a some- 
what different fungus is generally found, known under the name 
Botryomyces. Man is at times infected from the bovine species, excep- 
tionally by a human subject, nearly always through the grain which 
he has chewed or with which he has been pricked. 

The studies of recent years have had a tendency to divide the his- 
tory of actinomycosis, or at least to admit the action of a whole 
series of analogous but not identical parasites. Poncet and Dor have 
cited facts of this kind. Vincent has shown that the disease desig- 
nated by the name of pied de Madura, Madura foot, particularly fre- 
quent in India, Algeria, and America, is due to an analogous vegetable 
parasite, Streptothrix Madurce. 

Among the principal pathogenic streptothrices we shall simply men- 
tion Streptothrix asteroides (Eppinger), which has been quite fre- 
quently observed in abscesses of the brain, of the meninges, and of the 
kidneys; Streptothrix Foersteri, found in the form of agglomerated 
filaments in the calcareous concretions of the lachrymal duct; and 
particularly Streptothrix farcinosa (Nocard), which produces in 
cattle a disease improperly called farcy (glanders), which is not to be 
confounded with the glanders of the horse or of man. 

The Mucor group also contains a few pathogenic species which are 
of interest. Such is Mucor corymbifer, well studied experimentally by 
Lichtheim, and found in man by Paltauf . 

Mycomycetse. — Mycomycetae comprise aspergillus, penicillium, 
and saccharomyces. The most important among Aspergilli is As- 
pergillus fumigatus. It vegetates as a simple saprophyte on hemp, 
and induces pulmonary lesions in those subjects who chew the grains 
for feeding pigeons. A few but exceptional cases of aspergillosis of 
the kidneys, skin, cornea, nose, and pharynx have been recorded in 
man. In a pulmonary abscess presenting certain of the characters of 
actinomycosis, Wheaton found a parasite which he compares with 
Aspergillus niger. This species is not generally considered pathogenic. 
Observations and experiments nearly always show that it is Asper- 
gillus fumigatus or glaucus that is concerned. 

A widely distributed vegetable, Penicillium glaucum, which is gen- 



ANIMATE AGENTS 115 

erally a simple parasite, may, however, occasion general infections. 
The spores injected into the veins of a rabbit give rise to the develop- 
ment of a pseudo-tuberculosis. 

Eecent studies have drawn attention to the pathogenic role of 
Blastomycet^:. We have long known the action of one of them, 
Oidium albicans or Saccharomyces albicans. This parasite produces 
upon the mucous membrane of the mouth a lesion described under the 
name of aphthae or thrush. It is a local affection. However, in certain 
cases, oidium invades the organism, and in man produces a true general 
infection. At the autopsy, oidium nodules are found in the brain, 
kidneys, and lungs. Similar results have been obtained in animals, 
and these findings have thrown considerable light upon the mechan- 
ism of nonbacterial infections. 

The interest of blastomycetae is increased by recently published 
researches which establish the fact that these fungi are encountered in 
man much more frequently than was formerly believed. It will be 
seen in another chapter what an important role is attributed to them 
in the genesis of tumours. 

Protozoa. — Along with vegetable microbes are to be classed the 
animal microbes. We must place in this group the rhizopods and 
sporozoa, which alone are of importance in human pathology. 

Among the Khizopods we shall mention amcebm, which have been 
met with in the tartar of the teeth, in gingival abscesses, and in the 
vagina. Their importance has increased since the studies of Loesch, 
and particularly of Kartulis, have shown their presence in the intes- 
tines of dysenteric patients. Is it to be concluded that the Amaba coli 
is the cause of dysentery, and that it is also capable of producing the 
hepatic abscess consecutive thereto? This question is not yet solved, 
although an answer in the affirmative is quite probable. 

The Sporozoa are divided into the gregarinae and psorospermiae. 

The gregarinae represent parasites which are mostly found in in- 
vertebrates. Of late they have been observed in mammalia. Pfeiffer 
says he has found them in man in cases of smallpox, in vaccinia, scarlet 
fever, and herpes zoster; but their pathogenic function is by no means 
established. 

Psorospermiae possess much greater interest. With this group are 
classed the coccidia* which were first studied in animals. They are 

* Besides the coccidia, psorospermiaB include : 

(1) Myxosporidia, which are encountered in fish and which we have observed in 
the liver of a mouse. 

(2) Sarcosporidia (Miescher's tubes, Rainey's tubes), which invade the muscles 
of various mammalia. Rosenbergen found them in the myocardium of a woman 
forty years old. 

(3) Microsporidia, which inhabit worms and insects, and produce in silkworms 
the disease designated by the name of pebrine. 



116 INTRODUCTION TO THE STUDY OF MEDICINE 

frequently met with in the liver of rabbits, where they invade the 
biliary passages and give rise to epithelial and connective-tissue pro- 
liferations. Observed several times in the intestine, liver, kidneys, 
and pleura of man, coccidia are at present often looked upon as the 
cause of cancer. This conclusion, to which we shall again refer when 
speaking of tumours, is supported only by histological proofs. No one 
has as yet succeeded in cultivating the parasites, still less in inoculat- 
ing them. Lively discussions have therefore arisen on the subject, 
many scientists considering that the forms described as coccidia repre- 
sent simply degenerated cells. 

It is with a group allied to the coccidia that most naturalists class 
the parasite of malaria, Laveran's hematozoon, Plasmodium malarice; 
Laverania malarice, as it is justly called in foreign countries. Al- 
though it has not been possible to isolate and cultivate the parasite, 
observations are now so numerous that there can no longer be any 
doubt as to its etiological significance. The element discovered by 
Laveran certainly is the causative agent of malaria. It lives within 
the red blood corpuscles and presents itself under the various forms of 
spherical bodies, spherical flagellated bodies, and also of crescents and 
rosettes. 

Summary and Classification of the Infectious Agents. — If we con- 
sider the results which have been obtained by the study of patho- 
genic agents in infectious diseases, we may conclude that wonderful 
discoveries have been made. To-day nearly all diseases have their 
microbe. Those diseases in which the pathogenic agent is as yet 
unknown are not numerous, but, curiously enough, they belong to 
that class the infectious nature of which is not a matter of much 
doubt, and whose contagion is best established — e. g., the eruptive 
fevers, measles, scarlet fever, smallpox, varicella, vaccinia, the clearly 
infectious skin diseases like herpes zoster and polymorphous ery- 
thema, and those diseases which are never transmitted otherwise than 
by direct contact — rabies and syphilis. 

A. Nonspecific Bacteria. 
Micrococci. 

Staphylococcus. 

Aureus. 

Citreus. 

Albus. 
Streptococcus. 
Pneuraococcus. 
Tetragenus. 



ANIMATE AGENTS 117 

Bacilli. 

Colon bacillus. 

Paracolon bacillus. 

Bacillus of psittacosis. 

Pneumobacillus. 
Bacillus septicus putidus. 
Bacillus of hemorrhagic septicaemia. 
Proteus vulgaris. 
Bacillus pyocyaneus. 
Leptothrix buccalis. 

Specific Bacteria. 

Micrococci. 

Gonococcus. 
Micrococcus of mumps. 

Bacilli. 

Bacillus anthracis. 
Bacillus of glanders. 
Bacillus of typhoid. 
Bacillus of diphtheria. 
Bacillus of influenza. 
Bacillus of tuberculosis. 

Bacillus of human tuberculosis. 

Bacillus of avian tuberculosis. 

Bacillus of fish tuberculosis. 
Bacillus of leprosy. 
Bacillus of bubonic plague. 
Bacillus of yellow fever. 
Bacillus of soft chancre. 
Bacillus of tetanus. 
Bacillus of gaseous gangrene. 

Bacillus of symptomatic anthrax. 
Bacillus of rheumatism. 
Spirillum of recurrent fever. 
Bacillus of cholera. 

B. Phycomycet^e. 

Streptothrix. 

Streptothrix bovis (actinomyces). 
Streptothrix Madurae, asteroides, Foersteri. 
Streptothrix farcinosa. 

Mucor. 

Mucor corymbifer. 

C. Mycomycet^. 

Aspergillus. 

Aspergillus fumigatus. 
Aspergillus glaucus. 



118 INTRODUCTION TO THE STUDY OF MEDICINE 

Penicillium. 

Pencillium glaucum. 

Saccharomyces. 

Saccharomyces or Oidium albicans. 



D. Protozoa. 



Bhizopoda. 

Amoeba coli. 

Sporozoa. 

Coccidia. 
Hematozoa. 

Plasmodium malariae. 



CHAPTER VII 

ANIMATE AGENTS (Concluded) 

Distribution of microbes in water, soil, and air — Resistance of microbes to exter- 
nal agents — Antiseptics — Distribution of microbes in living beings — Role of 
microbes normally inhabiting the organism — The microbes of the alimentary 
canal — Gastrointestinal fermentations and putrefactions. 

Distribution of Microbes 

Water, as is well known, contains a great number of microbes; 
rain, snowflakes, and hailstones collect some of them in the atmos- 
phere. There is no pnre water except spring water at its source. 
Water containing from 50 to 160 bacteria per cubic centimetre is 
considered an excellent drinking water. These figures are much ex- 
ceeded in the majority of rivers, especially when they have passed 
through a city; these water courses, however, possess the property of 
spontaneously purifying themselves. A very simple observation proves 
this : it suffices to examine the Seine below the collector of Asnieres ; 
the water, overcharged with organic matters, is brownish, of a dis- 
agreeable odour, and at every moment gas bubbles burst on its sur- 
face, evidencing the intensity of fermentations going on. A few kilo- 
metres farther down the water again becomes limpid. 

The following figures offer examples in this regard : The Isar, 
before passing through Munich, contains 305 bacteria per cubic centi- 
metre; at its issue from the city, when it has received the products 
of sewers, it contains 12,600; 13 kilometres farther down, without 
having received any tributary, the figures fall to 2,400 per cubic 
centimetre. 

Natural depuration is produced equally in reservoirs. The water of 
the Thames, for example, contains 1,437 bacteria. It contains only 318 
after its passage into a first reservoir and 177 at its issue from a 
second. 

In rivers the agitation of the waters causes the microbes to unite 
with solid particles, and thus some are destroyed. If we take water 
containing 155 bacteria and agitate it with some chalk added in the 
9 119 



120 INTRODUCTION TO THE STUDY OF MEDICINE 

proportion of one fifth, there will remain only 10 ; with charcoal pow- 
der, the quantity falls from 8,000 to 60 ; with pulverized chalk, the re- 
sults are still more striking — the water is sterilized, even when the 
number of microbes was so great that it was impossible to count them. 

More important is the action of the sun, the rays of which exert 
an inhibitory influence on bacteria, as has been proved by a great num- 
ber of experimenters. Pansini introduced a few drops of a culture of 
asporogenic anthrax into water which he submitted to the action of 
the sun; then the number of bacteria per cubic centimetre was 2,520; 
at the end of twenty minutes it fell to 130 ; at the end of half an hour, 
to 44; after forty-five minutes there were none found. 

The results are identical with other microbes. Procaccini took 
sewer water containing from 300,000 to 420,000 bacteria per cubic 
centimetre and submitted it to the action of the sun. At the end of 
the day the liquid was sterile. 

Here is another experiment, which realizes the conditions perfectly. 
The water of the Isar, before its passage to Munich, was studied by 
Buchner at different hours of the same day. The highest figure was 
found at 4 a. m. ; bacteria had multiplied during the night and their 
number reached 520 per cubic centimetre. The minimum was ob- 
taned at 8 p. m. ; sunned all day, the water did not contain more than 
five bacteria per cubic centimetre. 

Among the pathogenic microbes most frequently encountered in 
water, we must mention the colon bacillus, typhoid bacillus, staphylo- 
coccus, streptococcus, the bacillus of gaseous gangrene, and, in certain 
cases, the anthrax bacterium, the vibrio of cholera, etc. Once in water, 
microbes can not come out of it ; consequently, they can not get access 
to our organism except through ingestion. When the level sinks, they 
are deposited upon the uncovered soil and are then easily disseminated. 
Pettenkoffer has made an application of this result to his celebrated 
theory on the variations in the level of subterranean waters. Accord- 
ing to him, when the level sinks, typhoid fever increases; when it 
rises, it decreases. Unfortunately, many exceptions have been re- 
corded; in some cases the variations of typhoid fever have occurred 
just in the contrary order. 

The soil contains a great number of bacteria, some of which are 
indispensable to vegetation. The works of Schloesing, Muntz, and 
Winogradsky have established their intervention in nitrification. For 
us, as we are considering the pathogenic phenomena, it suffices to know 
that pathogenic microbes are found in the soil: the bacilli of tetanus 
and of gaseous gangrene, the microbes of suppuration, and in certain 
cases the bacilli of typhoid fever, of tuberculosis, of anthrax, and of 
cholera. To this list should be added the saprophyte agents, which, 



ANIMATE AGENTS 121 

although inoffensive of themselves, may, when they enter our tissues, 
favour the development of pathogenic agents. 

It is easy to understand that in most cases the soil is contaminated 
with products emanating from diseased men and animals; that it is 
not more infected, is due to the germicidal action of the sun's rays, 
which rapidly destroy the microbes remaining on the surface ; but they 
act with less energy upon those which have sunk into a certain depth. 
One might believe that the latter are no longer capable of harm; un- 
fortunately, this is not so, for they may, under certain conditions, be 
brought up to the surface. This is what was . brought out by the 
celebrated researches pursued by Pasteur on the etiology of anthrax 
in the infected districts of Beauce, then designated under the 
name " cursed fields/' It is to be noted first that animals or 
their cadavers affected by anthrax never contain spores; the bac- 
teria would then be speedily destroyed, if blood or liquids con- 
taining them were not spread on the external mucous membranes and 
integuments and did not at the same time fall on the soil. Once out 
of the organism, bacilli rapidly give birth to spores, some of which con- 
taminate the soil; others, developing on the cadavers, are buried with 
them. Then, according to a theory, arrive the earthworms, which 
ingest the spores, raise them to the surface, and, depositing them in 
their excretions, spread them upon the surface of the soil. They may 
afterward be transported and disseminated far off by wandering ani- 
mals like the slugs, which in one day travel a great deal (Karlinski) ; 
or they may be swallowed by insects, some of which, provided with a 
sting, act as agents to inoculate man. 

Being thus spread upon the surface, the spores contaminate the 
vegetable growth; so herbivorous animals are infected by eating the 
plants. The infection takes place in the mouth when the mucous 
membrane is scratched by the spikes, or in the intestine. 

The researches which have been made with the typhoid bacillus 
have established that this microbe is quickly destroyed on the surface 
of the soil. It does not resist the action of the sun, but at 50 centi- 
metres of depth it finds excellent conditions of resistance and may 
retain its vitality for over five months. 

The number of microbes diminishes in proportion to the depth 
below the surface; the maximum is at 50 centimetres, and below 3.5 
or 4 metres there are none to be found. 

There remains a last question. Can the microbes of the soil invade 
vegetables? They can, according to Dr. Galippe. He has recorded a 
great number of experiments which have raised lively controversies. 
The problem is not yet solved; but, in view of its great practical in- 
terest, it deserves to be studied anew. 



122 INTRODUCTION TO THE STUDY OF MEDICINE 

The dust of apartments, tapestry, woodwork, and floors contain 
numerous pathogenic microbes. In hospital wards, in cases of epi- 
demics, there have been found between the planks of the floor the 
microbes of tetanus, erysipelas, pneumonia, and diphtheria. The same 
is true as regards tuberculosis; every author cites the researches of 
Cornet, who, in a room occupied by a consumptive, found that the dust 
obtained by scratching the wall, when inoculated into the peritoneum 
of a guinea pig, induced tuberculosis. 

The air serves much less to transmit infections than the soil, and 
still less than the water. It contains, however, a great number of 
microbes, as shown by the following figures, obtained by Dr. Miquel, 
which at the same time show clearly the considerable variations of 
the numbers depending upon the place : 

In the sea, at 100 kilometres from the coast 0.6 

Altitude of 2,000 metres 3 

Summit of Pantheon 200 

Observatory of Montsouris 480 

Rivoli Street (in Paris) 3,480 

New house 4,500 

The air of sewers of Paris 6,000 

Old house 36,000 

Hotel-Dieu (hospital) • 40,000 

Pitie Hospital 79,000 

One may be surprised, in perusing this list, to see that the air of 
sewers contains but a slightly greater number of microbes than the 
air of a new house, and six times less than that of an old house. It 
is because the innumerable bacteria contained in water can not invade 
the air. It has been experimentally shown that a current of air pass- 
ing over a contaminated liquid is not charged with microbes. The 
reverse opinion once prevailed; it was at one time believed that the 
air served as an intermediary between the water and our organism, 
and in support of this idea the events of an infectious character 
consequent on the inhalation of gases escaping from sewers or cess- 
pools were cited. In reality, the mechanism is more complex: the 
gases act by disturbing the economy and by reducing its resist- 
ance; they thus permit the development and exaltation of patho- 
genic germs which, until then, vegetated as simple, inoffensive 
parasites. 

The various results above recorded have but a relative value; very 
notable variations occur every day in the same place. During the hot 
season microbes increase, to reach their highest figure in the month of 
July; the minimum occurs in December. Their numbers diminish 
after a rainfall which carries them toward the soil; they diminish 



ANIMATE AGENTS 123 

equally under the influence of the sun's rays, the germicidal power of 
which has already been referred to. 

Eesearches have in most cases been limited to a simple counting of 
the microbes of the air, regardless of the proportion of pathogenic 
agents. But clinical observations suffice to inform us in this regard. 
It is admitted that typhoid fever may be transmitted through the air 
far more rarely than by water. The same applies to eruptive fevers, 
but it is to be noted that this mode of propagation is rare and 
occurs within a restricted zone. The virus of measles hardly extends 
beyond 4 metres, that of scarlet fever is perhaps a little more diffusible. 
As to smallpox, the better we study the march of epidemics the more 
we are convinced that contamination takes place in most cases, if not 
always, by direct contact. 

One of the infections which are transmitted most frequently 
through air is tuberculosis. The particles of desiccated expectoration 
are swept by the wind and penetrate the respiratory channels, and this 
accounts for the frequency of pulmonary lesions. 

The air has often been supposed to play a part in the transmission 
of surgical infections; it is to-day demonstrated that erysipelas, septi- 
caemia, and gangrene are generally propagated, not through the air, 
but by the hands of the surgeon and his assistants, by the instru- 
ments and dressing material. The same is true of puerperal fever: 
women attacked with erysipelas may be confined, even in an isolation 
ward devoted to the treatment of this infection, without becoming 
septicemic, provided necessary care and precautions be taken. 

One of the infections most frequently propagated by the air is ma- 
laria. The hematozoon may be transported to great distances from the 
marshes where it led its saprophytic life; but an obstacle of land, a 
wall, a cluster of trees suffices to arrest its passage. 

Eesistance of Microbes 

Microbes are submitted to a certain number of destructive causes, 
which may, according to their intensity, produce three different 
effects : functional modifications, a diminution in numbers, or a com- 
plete destruction. It is because the cultures are not homogeneous that 
the number can decrease; if all the individuals possessed the same 
vitality, all would perish at the same time. 

The resistance of microbes varies, on the other hand, according as 
the cultures do or do not contain spores : if they do not, resistance is, as 
is known, much less marked. 

The agents capable of doing harm to bacteria are also divisible into 
four groups : Mechanical, physical, chemical, and animate agents. 

Contrary to what has often been asserted, mechanical agents pos- 



124 INTRODUCTION TO THE STUDY OF MEDICINE 

sess but little action. We can not admit, for example, that the varia- 
tions of atmospheric pressure can modify the activity of the patho- 
genic bacteria, increase or diminish their virulence, and thus explain 
the epidemic temperament (genie epidemique) . The contrary opinion 
finds its origin in the erroneous interpretation of exact experiments. 
It has been shown, in fact, that certain compressed gases exert a 
noxious action on microbes; but in this case the effect is not simply 
due to an increase of pressure; the phenomena are much more com- 
plex. 

If, for example, we make the oxygen act under a pressure of 10 
atmospheres, we may kill the Bacillus anthracis; still, it is necessary 
to prolong the contact for a very long time. When the microbe is not 
a spore-bearing one, less than eight days will not suffice; when it 
does bear spores, death does not occur even at the end of twenty- 
one days. 

Carbonic acid appears to be more energetic. According to 
Fraenkel, Seltzer water is sterilized in the siphons. D'Arsonval has 
seen a certain number of bacteria perish under a pressure of 60 atmos- 
pheres. 

From all these researches it may be concluded that oxygen and car- 
bonic acid can kill microbes, provided the pressure be considerable. 

To make evident the true action of pressure, we have inclosed vari- 
ous microbes in rubber tubes which have been plunged in water or in oil. 
By compressing the liquid to 2,000 kilogrammes per square centi- 
metre, we observed no modification of the four species employed: 
streptococcus, staphylococcus, colon bacillus, non-spore-bearing and 
spore-bearing anthrax. 

Going up to the strongest pressures which one could reach — that is, 
to 3,000 kilogrammes (2,903 atmospheres) — we obtained the follow- 
ing results: Colon bacillus and Staphylococcus aureus have experi- 
enced no disturbance; the non-spore-bearing anthrax, sown in a fresh 
medium, developed more slowly than it habitually does, and proved 
less virulent than before compression; the spore-bearing anthrax was 
slightly attenuated; streptococcus vegetated less luxuriantly, less rap- 
idly, and furthermore lost part of its toxic action. It is necessary, 
then, to reach colossal pressures in order to observe some, anyhow 
little marked, modifications in the vitality or the properties of bacteria. 

It had been thought, after the researches of Horvath, that slight 
movements or oscillations of the culture medium prevented the devel- 
opment of microbes. Further experiments have not confirmed this 
result ; the effects have been variable and inconstant. For our part, we 
have obtained no results by submitting cultures to repeated shocks 
reaching 200 to 250 kilogrammes per square centimetre. 



ANIMATE AGENTS 125 

Physical agents have a far greater importance, at least some of 
them. Some, for instance cold, are very well borne. We have already 
said that microbes are found in ice. Dr. Raoul Pictet submitted bac- 
teria to temperatures as low as — 110° and even — 200° C. without 
succeeding in killing them. Professor d'Arsonval plunged some into 
liquefied air, without causing them to lose their power to vegetate. It 
is possible, however, to do harm to bacteria even with less low tem- 
peratures, by submitting them to successive freezings and tha wings; 
their numbers notably diminish in these conditions. 

Heat has a much more marked action. There are undoubtedly cer- 
tain species, notably those of hot springs, which seek heat and vegetate 
best at a temperature of 70° and 74° C. This is, however, an excep- 
tion. Bacteria are easily destroyed by heat, but effects vary according 
to several conditions, as usually the spores prove much more resistant 
than the adults. All other conditions being the same as regards the 
culture, heat is more destructive when microbes are contained in a 
liquid medium than when they are dried up. Finally, the action of 
heat is considerably favoured by the presence of air, which produces 
oxidations unfavourable to bacteria. 

The multiplicity of conditions intervening at the same time as 
heat explain the often considerable differences obtained by experiment- 
ers. The figures given have but a relative value; they nevertheless 
present a certain interest. 

Let us take, for example, the tubercle bacillus : plunged into water 
at 60° C, it is still living at the end of twenty minutes ; into water at 
70° C, at the end of ten minutes. Boiling water, at 100° C, kills it in 
five minutes. If dry heat is brought to act, the bacilli resist a tem- 
perature of 100° C. for several hours. 

The differences are the same for anthrax. According to Dr. Mo- 
mont, anthrax blood, desiccated in a vacuum, remains virulent after a 
sojourn of an hour and a half in an oven at 92° C. ; the moist blood 
is sterilized at 55° C. in one hour. To kill the spores, we must submit 
them, according to Koch and Wolffhiigel, to 107° C. for five minutes, 
when they are moist; if dry, they resist 120° C. for four hours; to 
make their destruction sure, we must leave them three hours at 140° 
C. It is true that Massol finds less elevated figures. A temperature of 
100° C. kills the spores at the end of five or six minutes. 

The influence of air is made apparent from Dr. Roux's experiments. 
Submitted to the combined action of air and a temperature of 70° C, 
spores succumb in 60 hours; protected from air, they still live at the 
end of 165 hours. 

We have already shown, with respect to microbes of the soil, the 
important part played by light. The blue and violet rays act most 



126 INTRODUCTION TO THE STUDY OF MEDICINE 

energetically; but, as in the case of heat, the action of the light is 
favoured by moisture and by air. Dr. Momont has shown that anthrax 
spores perish after 48 hours of insolation when they are in contact 
with air; inclosed in a vacuum, they are still living after 110 hours. 
The action of light may be evidenced by the following experiment : A 
few drops of an anthrax culture are spread upon a gelatine plate, which 
is then covered with a glass upon which pieces of black paper are 
pasted; on exposure to the light, development takes place in the pro- 
tected parts and the bacteria exactly reproduce the designs figured by 
the pieces of paper. 

The action of light is more complex ; for, besides the noxious influ- 
ence exercised on bacteria, the modifications of the medium are to be 
taken into account ; sunned bouillon becomes unfit for cultivation. 

In cases where life persists, functional modifications supervene: 
chromogenic microbes cease to produce pigment, and pathogenic agents 
become attenuated. 

We shall not dwell upon the effects of electricity. In the old ex- 
periments the currents employed produced heat or electrolysis, and the 
effects obtained were of a thermal or chemical order. Those authors 
who have been on their guard against these causes of error have not 
been able to detect a direct action of electricity on microbes. 

The chemical agents that act upon bacteria are called antiseptic 
agents. Among the gaseous bodies, it suffices to mention ozone, which, 
as is known, is often found in the air in great quantities. Its action 
is very intense, at least on the adult elements; the non-spore-bearing 
anthrax is killed within five hours, but the spores perish only at the end 
of three or four days. 

The antiseptics, properly so called, when used in minute doses, have 
the very curious property of stimulating the activity of microbes; 
under their influence, the chromogenic bacteria produce a greater quan- 
tity of pigment. In increasing the dose of the antiseptic, we see the 
chromogenic power diminish and disappear; then vegetation grows 
slower, ceases, and finally the microbe is killed. 

Carbolic acid is one of the substances most frequently employed. 
In a 1-per-cent solution it kills the non-spore-bearing bacterium in 
ten seconds; if the element is spore-bearing, life persists after the 
continued intervention for thirty-seven days of a solution five times 
stronger. 

In order to increase the action of antiseptics, it is well to raise the 
temperature of the medium; this is an element of capital importance 
from a practical standpoint. For disinfecting purposes hot solutions 
must be employed. The anthrax spores, for example, resist 5-per-cent 
carbolic acid at the surrounding temperature, but they are killed in the 



ANIMATE AGENTS 127 

same solution in two hours if the temperature reaches 55° C, and in 
three minutes if it is raised to 57° C. 

By submitting a microbe to the influence of antiseptics during sev- 
eral successive generations, we can permanently modify it and deprive 
it of some of its properties. Thus are created non-pigment-forming, 
non-spore-bearing varieties, and, what is more important, the virulence 
is made to disappear and vaccines are obtained. 

The action of animate agents upon bacteria now remains to be con- 
sidered. In a great number of cases, two or more microbes vegetate 
in the same medium. Sometimes they assist each other; thus, for 
example, an aerobic microbe, by appropriating to itself the oxygen, 
will facilitate the development of an anaerobic. More frequently they 
antagonize each other; in cultures originally polymicrobic one species 
will little by little predominate and finally stifle the others ; a natural 
selection is effected. Moreover, microbes have frequently to struggle 
with the higher organisms, vegetable and animal, whether they occupy 
their integuments or penetrate into their interior. We are thus led 
to study the behaviour of bacteria toward higher beings. 

Distribution" of Bacteria in Living Organisms 

The distribution of microbes in the air, soil, and water suffices to 
explain their presence on all the exposed parts of our bodies. They are 
found in great number upon the skin; they live there as inoffensive 
parasites; the horny epidermis, further protected by a layer of fat, 
opposes to them an impassable barrier. 

With each inspiration, the air causes a great number of bacteria 
to penetrate the respiratory passages. They are retained by the hair 
in the nasal orifices and by the vibratile cilia of the mucous mem- 
brane. Others are fixed by secretions; they become pasted, as it were, 
to the moist tissues. Therefore the farther we recede from the natu- 
ral orifices the smaller the number of bacteria do we find. At the level 
of the pulmonary alveoli, often at the level of the bronchi or even of 
the trachea, the air is bacteriologically pure. In again passing through 
the respiratory tract, at the moment of expiration, the air does not 
take up the parasites which it has deposited, for, as we have already 
said, these can never leave the liquid media which encompass them. 
The expired air, therefore, contains no microbes. 

It may be inquired : What is the fate of the bacteria that are thus 
deposited and that might become harmful, if only by their number? 
Fortunately, the respiratory apparatus is provided with various means 
of protection. The secretions act mechanically and wash, so to say, 
the mucous membrane; a certain number of bacteria are thus thrown 
out. Others are destroyed by the nasal mucus, which, as has been 



128 INTRODUCTION TO THE STUDY OF MEDICINE 

shown by Lermoyez and Wurtz, possesses germicidal powers. In other 
words, the secretions exercise a sort of antiseptic action. The re- 
mainder are picked up and devoured by certain cells called phagocytes, 
which are very numerous in those localities where lymphoid tissue 
abounds, and at the level of the pulmonary alveoli. 

Bacteria are much more numerous in the digestive canal. Ingested 
with the food and beverages, they reach the stomach, where, according 
to certain authors, the acid has the property of destroying them. This 
assertion, based upon results obtained by means of artificial digestion, 
explains the frequency of infection when the subject is fasting, when 
the stomach is altered, or the gastric juice is neutralized by an alkali. 
It seems, however, that the protective role of the stomach has been 
somewhat exaggerated; for counts which have of late been made show 
that this portion of the digestive tract contains numerous bacteria, 
even more than the duodenum. 

Having reached the intestine, the microbes here find the best con- 
ditions for their existence. The aliments we ingest serve for N their 
nutrition; the heat of our digestive tract offers them the advantages 
of a well-regulated oven; the secretions which flow are far from being 
germicidal, since they contain substances favourable to their develop- 
ment. We may therefore say that the alimentary canal is the paradise 
of microbes, and that they can multiply energetically, as is shown by 
the following figures, taken from the interesting researches of Gilbert 
and Dominici. There are found in the stomach 50,000 microbes per 
cubic millimetre; then the figure suddenly falls; at the origin of the 
duodenum there are only 30,000; the number progressively rises until 
the end of the bowel is reached, where it attains its highest point — 
namely, 100,000 per cubic millimetre. In the caecum another fall 
occurs; throughout the length of the large intestine there are only 
25,000 to 30,000 microbes per cubic millimetre. By taking account of 
the quantity of matter contained in the digestive canal, we arrive at 
the respectable total of 411,000,000,000 microbes. 

Each day man rejects a certain number of bacteria in his faeces. 
In health the quantity varies from 12,000,000,000 (Gilbert and Domi- 
nici) to 40,000,000,000 (Vignal). 

According to some authors, these microbes play a salutary part; 
they perform a second digestion, complementary to that accomplished 
by the digestive juices. This idea, developed by Dr. Duclaux, has led 
to the supposition that perhaps life would be impossible without the 
aid of these collaborators, which are to animals what the microbes of 
nitrification are to plants. The hypothesis is seductive, and it is 
doubtless very interesting to study what would become of animal life 
without the intervention of bacteria. An experiment, difficult to real- 



ANIMATE AGENTS 129 

ize, has, however, been conducted by Nuttal and Thierfelder. By 
means of a very ingenious contrivance these authors succeeded in 
breeding two guinea pigs protected from microbes. Unfortunately, the 
experiment lasted but eight days ; during this time, however, these ani- 
mals nourished just as well as the control animals left in the free air. 
It is evidently impossible to conclude what would happen later. These 
researches are worthy of repetition. 

Whatever be the solution employed, it is incontestable that mi- 
crobes cause our aliments to undergo profound transformations, some 
of which are similar to those of digestion, others differing therefrom 
in that the modification of substances is greater. 

The albumens are peptonized, but at the same time there are pro- 
duced amido agents, leucine, tyrosine, and particularly aromatic bodies, 
indol, phenol, and skatol. The last-named, slightly soluble, remains 
almost entirely in the faeces and gives to them their peculiar odour. 
Indol and phenol are reabsorbed, and, after certain modifications 
within the organism, are eliminated in the urine. Coincidently, there 
are produced volatile substances, carbonic acid, ammonia, sulphuretted 
hydrogen, methylmercaptan (a substance with a nauseous smell, enter- 
ing into ebullition at 21° C), of which one part is expelled by the 
anus, and another, being reabsorbed, is eliminated by the respiratory 
apparatus and the skin. Finally, there are formed ptomaines, which, 
from their chemical constitution, are analogous to vegetable alkaloids. 
With a view of recalling their origin and their toxic effects, the princi- 
pal ones have been denominated ptomatoatropine and ptomatomusca- 
rine. It is then easily understood that faecal matters are toxic. Ac- 
cording to Bouchard, the extract of 17 grammes suffices to kill 1 kilo- 
gramme of animal. 

The action on the other groups of aliments is less important from 
a pathological standpoint. The carbohydrates are transformed into 
alcohol — and this explains the presence of this substance in the organ- 
ism of animals — and into acids. The cellulose is attacked and the fats 
are broken up. 

Certain aliments, like milk, hinder fermentation; others favour it. 
Bouillon, meat, particularly veal, offer excellent culture media for bac- 
teria. Putrefactions reach their highest intensity when tainted ali- 
mentary substances are ingested. The use of venison, or of dishes 
made with ill-preserved cold meat, may often produce grave disturb- 
ances. These are particularly frequent in Germany, where they are 
described under the name botulism or allantiasis. They result from 
the ingestion of very large sausages, the central portions of which are 
incompletely cooked. This element contains perfectly formed pto- 
maines as well as microbes. Ptomaines chiefly serve to diminish the 



# 



130 INTRODUCTION TO THE STUDY OF MEDICINE 

resistance of the organism ; they favour the multiplication of microbes, 
and, after an incubation period of from twelve to fifteen hours, disturb- 
ances make their appearance. These are manifested by vomiting, a 
horribly fetid diarrhoea, and, in the grave forms, cutaneous eruptions, 
nervous manifestations, dizziness, and diplopia. Lastly, in certain 
cases, the temperature falls, the extremities grow cold, and the patient 
succumbs in collapse. 

Poisonings have been occasioned by the use of preserves. The cen- 
tral parts of the boxes are not always sufficiently heated and may con- 
tain dangerous microbes. 

Preserved fish, and particularly preserved lobster, have thus caused 
serious disturbances. The same is true of salted codfish; its dangerous 
character is indicated by the rosy colour which it presents and which is 
due to a fungus — viz., Beggiatoa roseo-perniciosa — which is not dan- 
gerous by itself, but is accompanied by putrefactive bacteria. 

Milk may also be altered; it contains a poison studied by Vaughan 
— tyrotoxine — which produces serious disturbances, notably in chil- 
dren. 

The intestinal putrefactions, when exaggerated by some cause or 
another, occasion a whole series of disturbances. Locally, an irritation 
of the bowel is produced, which is expressed by expulsive colics and 
diarrhoea, and nauseous evacuations. Part of the volatile principles is 
absorbed and is eliminated by the breath and by the sweat, which takes 
on a fetid odour; there are present at the same time lassitude, dizzi- 
ness, and headache — all phenomena denoting intoxication of the 
organism. 

Eeciprocally, in case of constipation, the intestinal products are 
reabsorbed; the manifestations are similar, but less marked, for the 
faecal matters are harder and absorption is less easily effected; the 
symptoms are again dizziness, headache, fatigue, and fetid breath and 
sweat. 

Generally these disorders are not of serious import in normal 
individuals ; but not so with certain patients, notably those having re- 
cently undergone an operation, and, above all, with puerperal women. 
A febrile state is observed, at times disquieting, which yields to the 
influence of an enema, a purgative, or an antiseptic. 

In still severer cases there occurs intestinal obstruction, in which, 
among numerous disturbances, several are referable to the reabsorption 
of toxines. 

When the stomach is profoundly affected, and notably in dilatation 
of this organ, the exaggeration of putrefaction gives rise to a series 
of morbid manifestations. On awakening, the patient feels more tired 
than at bedtime. He suffers from headache and dizziness ; the passage 



ANIMATE AGENTS 131 

of toxines through the kidneys induces albuminuria; their action on 
the bones produces various alterations, such as nodes at the level of 
the second phalanx, and osteoporosis. In childhood rickets is the con- 
sequence of disturbances of intestinal digestion which are so frequent 
at that age. 

Two still graver symptoms may depend upon exaggerated gastric 
fermentation : tetany, which is sometimes fatal, and diacetaemic coma, 
which we shall study more fully in connection with diabetes. 

It is easy to understand that in a great number of general dis- 
eases, markedly in infections, intestinal putrefactions increase by 
reason of the fact that the means we possess for preventing them 
decrease. .. 

The digestive canal can expel microbes by the same procedures as 
other parts of the organism; the intestinal and pancreatic juices and 
the bile, although not possessing any antiseptic property, act as cleans- 
ing agents and at once reject microbes and toxines. If bacilli tend 
to pass through the mucous membrane, they are arrested by the lym- 
phoid organs — solitary glands and Peyer's patches — and by numerous 
leucocytes, which constantly travel in these regions, and can even make 
their way into the cavity of the intestine. 

If they escape these causes of destruction, microbes reach the lym- 
phatic glands and the liver, where new means of defence are found. 
If they pass beyond, they reach the lungs, which are also endowed with 
germicidal power. We thus see how many precautions are accumulated 
against the microbes of the bowels. 

Protection against microbic toxines is assured by the digestive 
secretions, which transform some of them, throw out others, and par- 
ticularly by a very special action of the intestinal mucous membrane. 
Taking up an idea of Stich, Denys and Brion have proved that the 
epithelial cells of the intestine destroy the microbic toxines; those 
that escape pass through the liver, which neutralizes some of them. 
But the protective function of this gland is quite variable. It is very 
pronounced with the toxines of certain varieties of the colon bacillus, 
but does not seem to be exercised upon poisons produced by other 
species. So, in many cases, the poisons pass onward, and are elimi- 
nated by the kidneys. Thus the toxicity of the urine chiefly depends 
upon intestinal putrefaction ; it varies parallel to this. 

There yet remain the volatile substances, sulphuretted hydrogen 
and methylmercaptan, which are eliminated by the lungs and the skin, 
imparting a foul odour to the breath and the sweat. It is to be noted 
that the liver intervenes here with great energy; numerous experiments 
prove that it retains and neutralizes considerable quantities of sulphu- 
retted hydrogen. 



132 INTRODUCTION TO THE STUDY OF MEDICINE 

Intestinal fermentation may be overcome by dietetics and by thera- 
peutics. 

It suffices to confine one's self to a milk diet in order to restrict 
putrefaction in the bowels. Gilbert and Dominici found in the faecal 
matters of a normal man 67,000 bacteria per cubic millimetre; after 
two days of milk diet, there were no more than 14,000 ; at the end of 
three days, 8,000, and of five, 2,250. Sterilized milk, by the way, gives 
no better results; at the end of ten days the stools contain 3,000 bac- 
teria per cubic millimetre. 

These differences, already very notable, appear still more marked 
when account is taken of the quantity of matters discharged. Placed 
upon a mixed diet, a man passes 175 grammes of faeces, containing 
12,000,000,000 bacteria ; under the influence of milk diet, the quantity 
falls to 73 grammes containing only 164,250,000 bacteria — that is, -fa 
of the original figure. 

Of the procedures furnished by therapeutics, we must first men- 
tion purgatives, the influence of which has been demonstrated by 
numerous experiments; one may employ saline purgatives, which expel 
the microbes, as well as calomel, which has the advantage of possessing 
a notable antiseptic action. 

To inhibit the development of microbes, one may resort to insolu- 
ble antiseptics which traverse the digestive canal without being ab- 
sorbed: naphthol, benzonaphthol, and betol are the substances gener- 
ally used. In order to prolong their action, it would be well to pre- 
scribe them in fractional doses. Benzonaphthol and betol are less 
active than naphthol, but they do not possess the acrid and burning 
taste of the latter. So they may be used in the cases of children. 

To these substances is often added subnitrate or salicylate of bis- 
muth. The subnitrate renders the stools thicker and exerts a chemical 
action. In contact with sulphuretted hydrogen, it is decomposed and 
gives rise to sulphide of bismuth, an insoluble body that neutralizes 
the harmful action of sulphuretted hydrogen. Salicylate of bismuth 
does not act quite as well, but it has the advantage of furnishing infor- 
mation concerning the intestinal putrefactions. The salt is decom- 
posed and the salicylic acid resulting therefrom passes into the urine, 
where it is easily detected by the addition of perchloride of iron, which 
yields a beautiful violet colour. This reaction does not occur when the 
production of sulphuretted hydrogen has ceased. 



CHAPTER VIII 
GENEBAL ETIOLOGY OF INFECTIONS 

Hetero- and auto-infections — Morbid contagion and spontaneity — Causes favour- 
ing infection: immunity and predisposition — Microbic associations — Modes of 
entrance of microbes — Modes of protection of the organism — Local lesion — 
Part played by lymphoid productions — Protective part played by certain 
organs— Importance of the liver and the lungs — Causes explaining microbic 
localizations: mode of entrance; physiological and pathological state of the 
organs. 

Infectious diseases may be produced in two ways : they may result 
either from the introduction into our organism of virulent germs com- 
ing from without, or they may be due to microbes that have their 
lodging within our bodies, and which become exalted under the influ- 
ence of various intercurrent causes. Infections may therefore be 
divided into two groups: Hetero-infections, recognising an external 
origin, and auto-infections, of which we carry the germs in ourselves, 
even under normal conditions. 

This division, which may be retained, has not an absolute value. 
It is evident that all microbes that live in us come from outside. But 
once introduced into our organism, they behave differently. Some 
remain in the condition of harmless parasites until the time when a 
morbific cause, diminishing our resistance, enables them to induce a 
disease. Others act immediately, and their introduction is soon fol- 
lowed by the appearance of morbid manifestations. Yet others hold a 
position intermediary between the two preceding groups. When they 
reach us, instead of remaining altogether inoffensive, they provoke a 
slight, circumscribed lesion, which is sometimes latent and often cur- 
able. While the pathogenic agent remains thus localized, even when 
nothing reveals its presence, the organism is always threatened by acci- 
dents ; on the slightest occasion the microbe becomes again aggressive 
and the local lesion is made the starting point of a more or less serious 
infection. 

Let us take some examples. Among the pathogenic microbes that 
may live for a very long time without occasioning any disorder, we find 

133 



13i INTRODUCTION TO THE STUDY OF MEDICINE 

staphylococcus, streptococcus, pneumococcus, and colon bacillus. Of 
microbes producing infection soon after they penetrate an organism, 
we may cite the agents of anthrax, hydrophobia, syphilis, and soft 
chancre. In the last group is placed the tubercle bacillus, which may 
for years locate itself in a ganglion without giving rise to any notable 
result. 

It is further to be noted that the same infection may be brought 
about in several different ways. Pneumonia, for instance, is due to 
pneumococcus, which vegetates in the mouth as a harmless parasite; 
let some accessory cause decrease the resistance of the organism, the 
microbe will invade the lung and provoke pneumonia. From this 
moment the exalted germ is able to attack other persons ; in this man- 
ner the disease born by auto-infection spreads by hetero-infection. 

Pathogenic microbes may be introduced in several different ways. 
There is, in the first place, direct inoculation. A virulent microbe 
comes to soil the surface of a wound, or penetrated with an instrument 
into the tissues. All wounds are not equally apt to be invaded by bac- 
teria. Those clean cut are seldom infected ; not that microbes are lack- 
ing on their surface, but they do not find conditions favourable for 
their development. Contused wounds represent, on the other hand, an 
excellent medium of culture ; the tissues being affected in their vitality, 
the cells are unable to prevent the multiplication of morbid agents. 

The microbes of suppuration, gangrene, and tetanus develop rather 
in the contused wounds. For other more virulent agents the slightest 
abrasion suffices for infecting the economy; such is the case with an- 
thrax, glanders, hydrophobia, syphilis, and soft chancre. Against 
these viruses our resistance is very weak, and inoculation is too fre- 
quently positive. There are, nevertheless, some very curious examples 
of immunity. Certain individuals do not contract venereal diseases, 
although they do not fail to expose themselves to contagion; others 
prove rebellious to vaccine, and, in this case, clinical observation has 
the value of a .laboratory experiment. 

The second mode of transmission of disease is represented by con- 
tagion. The microbe does not break in, but penetrates through the 
natural channels. 

Contamination may occur in different ways. In some cases there is 
contact of the healthy subject with the sick. In other instances the 
transmission is indirect ; it takes place through the atmosphere, objects, 
or persons who carry the microbe without being themselves con- 
taminated. 

Immediate contagion is a matter of evidence; but transportation 
by air is more conjectural. The latter has been imagined to explain 
the course of epidemics; as regards influenza particularly, it has been 



GENERAL ETIOLOGY OF INFECTIONS 135 

said that atmospheric transmission made it possible for this disease 
to pass in twenty-four hours from Berlin to Paris. In analyzing the 
facts, however, we perceive that epidemics do not go any quicker than 
our means of communication; they are propagated, not by the wind, 
but by direct contagion. 

Individuals who have taken care of patients, or simply approached 
them, may transport the disease. Certain epidemics of puerperal 
fever recognise no other cause. Still more frequently are the surgeon 
or his assistants to blame, who have not very carefully cleaned their 
hands, or have used dressing material, especially instruments, not well 
disinfected. 

In other cases contagion is explained by the persistence of morbid 
germs in rooms, on papers, tapestry, rugs, floor, and especially in 
clothing; sometimes also in vehicles which have served to transport 
patients. Hence the excellent measures taken for the disinfection of 
carriages and wagons. Disease may be transported also through let- 
ters. Graves's observation is well known: A young lady contracted 
scarlet fever through a letter which had been addressed to her by a 
friend of hers convalescent from this disease; the microbe had been 
transmitted through particles of scales falling from her hands. So in 
the isolation hospital of Aubervilliers letters are disinfected before 
they are sent to the post office : after perforating them by means of 
pins they submit them to the action of sulphur fumes. 

Although less frequent, transportation through the atmosphere is 
undeniable. Intermittent fever is thus transmitted; the majority of 
cases of pulmonary tuberculosis acknowledge the same origin. 

Lastly, the soil, and, above all, water are often contaminated with 
microbes proceeding from patients, and play a considerable part in 
the development of certain infections. It is through water that 
typhoid fever, cholera, and dysentery are propagated; it is in the soil 
that the germs of tetanus, gaseous gangrene, and anthrax spread them- 
selves. 

In cases of auto-infection there is no contagion; as already 
stated, the malady is generated spontaneously. Though the fact is of 
rare occurrence, it may be true as regards specific diseases, typhoid 
fever, for example. Military physicians have reported observations 
which seem to be absolutely demonstrative; soldiers have been seen to 
depart for manoeuvres and lodge in villages where typhoid fever had 
not been observed for years past; in consequence of fatigue, a sol- 
dier is attacked by the fever, then another, then a third, and a 
small epidemic takes place. The same fact is observed in permanent 
camps ; at the end of five or six weeks typhoid fever makes its appear- 
ance. A striking example is reported by Dr. Kelsch. During the war 
10 



136 INTRODUCTION TO THE STUDY OF MEDICINE 

of 1870 the German army was camping on both banks of the Moselle; 
the contingent on the right bank suffered from typhoid fever in the 
proportion of only 12 per 1,000 ; the one on the left bank in the pro- 
portion of 27 per 1,000. Yet the conditions of air, earth, and water 
were the same, except that on the left bank there was more crowding, 
a greater mass of men, and therefore worse sanitary conditions. What 
seems to be still more conclusive is the fact that typhoid fever has 
been seen to make its appearance on board a ship five or six weeks 
after it had left the land. Certain authors, convinced contagionists, 
have doubted the reality of these facts; others have attempted to 
explain them by a very seductive theory. Drs. Rodet and Eoux have 
argued that the typhoid bacillus is but a variety of colon bacillus, this 
common guest of our alimentary canal. If the resistance of the organ- 
ism be diminished, the disease sets in, spontaneously in appearance, 
but in reality by the exaltation of this parasite until then inoffensive. 
This ingenious conception has occasioned a great number of contra- 
dictory studies. But to-day we no longer need such a hypothesis, as, 
according to Reumlinger and Schneider, the typhic bacillus is found 
in the intestinal contents and f aecal matters of persons in good health ; 
this fact explains the apparently spontaneous development of the dis- 
ease, and its future transmission by contagion. 

Other well-defined infections may also appear spontaneously — for 
instance, diphtheria. Its development is perhaps explained by the pres- 
ence, in the buccal cavity, of a bacillus designated pseudo-diphtheric, 
which is often considered to be an attenuated variety of the Loeffier 
bacillus. The question has been put even with regard to gonorrhoea. 
Straus published a case alleged to have occurred without any con- 
tagion. But it is not safe in such cases to trust the assertions of pa- 
tients who, too often, are unwilling to confess how they have been con- 
taminated. 

It must be acknowledged that, even for diseases whose contagion 
is most frequently admitted, it is not always possible to discover the 
method of contamination. If a great number of persons attacked by 
measles, and especially by scarlet fever, were questioned, the majority 
would be unable to say where and how they contracted the germ 
of their disease. Hence some physicians think that scarlet fever, 
which they see occurring without any contamination, may originate 
spontaneously; they have attempted to eliminate this eruptive fever 
from the class of specific infections and to admit that it is owing to a 
common microbe — to streptococcus, for instance — which, according to 
their view, becomes exalted and acquires certain special properties; it 
preserves its new qualities for a certain length of time, and this ex-- 
plains the further propagation of the disease. 



GENERAL ETIOLOGY OF INFECTIONS 137 

Nearly all of the infections that originate spontaneously — viz., 
without any contagion whatever — are due to common bacteria, which 
become more virulent when our resistance grows fainter. Thus staphy- 
lococcus, an habitual guest of the skin, gives rise spontaneously, as it 
were, to abscesses, boils, and anthrax; streptococcus, vegetating in the 
mouth, provokes erysipelas and sore throat; pneumococcus produces 
bronchitis, broncho-pneumonia, and lobar pneumonia; colon bacillus 
causes enteritis, or, making its way into the liver, induces suppurative 
angiocholitis, etc. Microbes thus become educated; they learn how to 
overcome the resistance of the organism, and in the end constitute par- 
ticular races, apt to reproduce in others an affection analogous to or 
identical with the one which they have in the first instance provoked. 
Streptococcus, for example, which has acquired the property of causing 
erysipelas, will produce erysipelas by contagion. That which has de- 
termined angina, will reproduce angina. Although there are instances 
of a different evolution, it seems that, while being exalted, microbes 
acquire a certain specific power — that is, a certain aptitude for repro- 
ducing accidents of similar location and evolution. In this manner at 
the present day is morbid spontaneity explained, and the ulterior trans- 
mission of a first case, arising without any contagion, accounted for. 

Causes Favourable to Infection. — We are thus led to investigate 
the causes which, by diminishing our resistance, permit the develop- 
ment of infections. 

There is, first, a series of extrinsic causes in connection with re- 
gions and seasons. 

In some countries a certain infectious malady prevails endemically ; 
in others the disease can not become acclimated. Yellow fever, which 
fearfully ravages some countries of America, has never reached the 
Old World. If, perchance, a patient is found on board a ship arriving 
at a European port, no cases occur in the city. 

In some instances the exotic disease gets a foothold, as is the case 
with cholera; at times it assumes a character of exceptional malig- 
nancy ; such proved to be the case of measles transported to the Faroe 
and Fiji Islands. 

The influence of the seasons has long been recognised. It has been 
indicated by Hippocrates, and is clearly brought out by modern statis- 
tics. In a general way, infectious diseases, notably eruptive fevers, are 
specially frequent from March to July ; the minimum extends from Sep- 
tember to December. During the hot season gastrointestinal mani- 
festations are more frequently observed; during the cold season, tho- 
racic disorders. 

The hygienic condition of a country is a factor of obvious impor- 
tance. The number of infectious diseases has considerably decreased 



138 INTRODUCTION TO THE STUDY OF MEDICINE 

since the progress accomplished in the disinfection of lodgings and 
clothing, the creation of special hospitals for the isolation of patients, 
and the improvement of drinking water. Even typhoid fever has be- 
come less frequent. 

Morbid aptitude varies considerably with different races. The 
negroes are immune from certain infections, as yellow fever; even the 
mulattoes are safe, and in countries where the disease is endemic it is 
customary to say that a drop of black blood is the best of preservatives. 
The negroes are likewise little subject to malaria. They are, on the 
other hand, very susceptible to tetanus, and much inclined to develop 
chancroids on the slightest suppuration. 

The yellow race is predisposed to smallpox, which rages as an en- 
demic; their susceptibility is so marked that it is not rare to see re- 
lapses of this infection. 

Acute articular rheumatism is, so to say, allotted to the Caucasian 
race. 

Predispositions and immunities no less remarkable may be noted 
among different peoples of the same race. The Anglo-Saxons are very 
liable to sudor Anglicus, and especially to scarlet fever. But what is 
more curious is that the sensibility of the English to scarlet fever is of 
recent date. Sydenham, who was the first to describe this infection, 
considered it as very benign, hardly deserving the name disease — " vix 
morbi nomen." Graves also held the same view, but he, at a later 
period, saw the disease change its aspect and become very fatal. It is 
not right, therefore, to repeat that the gravity of scarlet fever is de- 
pendent on the race, since the disease was formerly benign. Nor can 
it be attributed to climatic modifications, for the English, when in 
France, are attacked by serious scarlet fever, while the French going 
to England develop a benign form. 

Veterinary medicine, even more than human medicine, furnishes 
numerous instances of predisposition and immunity characteristic of 
race. Algerian sheep are refractory to anthrax, and the black sheep of 
Bretagne are immune from murr. This last example brings us back 
to human medicine. Dr. Landouzy has much insisted on the frequency 
of tuberculosis among those inhabitants of Paris who present the char- 
acter of the Venetian type — that is, fine skin and reddish hair. 

If we pass from race to family, we meet with similar facts. There 
are families in which tuberculosis, or diphtheria, or erysipelas is notably 
frequent, and we speak, of course, only of cases of infections which 
develop without family contagion. 

There exist also numerous individual variations; persons have 
often exposed themselves to contagion, even to inoculation, without 
being contaminated. Vaccine has failed in a great number of cases. 



GENERAL ETIOLOGY OF INFECTIONS 139 

So in laboratories we see from time to time an animal that resists, 
while others apparently similar, placed under identical conditions and 
inoculated in the same way, all succumb. 

In certain cases individual immunity may be explained by what 
has been very justly called insensible vaccination. The inhabitants of 
Paris, for instance, do not, as a rule, contract typhoid fever; but indi- 
viduals arriving from the country are often attacked by it. It is be- 
cause Parisians, from infancy, have been little by little impregnated 
with the morbid germ; thus becoming progressively habituated, they 
have either experienced no disturbance at all, or symptoms too slight 
and vaguely characterized to be attributed to their true cause. 

It is in this way we must explain the disappearance of epidemics ; 
if the cases, at a given moment, grow less and less grave and more and 
more infrequent, it is because, little by little, the population has under- 
gone an insensible vaccination. The incontestable immunity of physi- 
cians is due to no other cause. 

We may ascribe to an analogous process the fact that an infection 
gradually loses its gravity in the course of centuries, or acquires an 
unusual malignancy when invading a population until then spared. 
Nothing is more interesting and instructive in this connection than the 
epidemics of measles of the Faroe Islands. The disease was imported 
there in 1846. Of the 7,782 inhabitants, 6,000 were attacked, only the 
old being spared. In 1875 the same disease invaded the Fiji Islands, 
and caused the death of 40,000 persons out of a population of 150,000. 

The resistance and predisposition of certain subjects are sometimes 
explained by their heredity. The sons of an arthritic person are pre- 
disposed to a series of nutritive affections, but they are refractory, or 
at least less susceptible, to tuberculosis. 

In certain cases, an individual comes into the world with an innate 
tendency, quite different from heredity; its cause is generally a par- 
ticular state of the parents at the moment of conception, and the 
state of the mother during gestation. We have observed, for example, 
a man and a woman of uncommon strength who had had three chil- 
dren : the firstborn and the youngest were very well constituted and had 
inherited the temperament of their generators; the second was poorly 
developed, remained feeble, and at the age of twelve years contracted a 
tuberculosis of which he died. Why did this child present such an 
inborn diathesis ? Why had not the hereditary characters been trans- 
mitted? Simply because at the moment of conception the father was 
convalescent from pneumonia, and this accidental sickness had suf- 
ficiently disturbed his organism to modify his progeny. Is there not in 
this observation, as conclusive as an experiment, the explanation of 
many a fact concerning family and race modifications ? 



140 INTRODUCTION TO THE STUDY OF MEDICINE 

The aptitude for contracting infectious diseases varies considerably 
with age. During intra-uterine life the foetus is exposed to some dis- 
eases whose germs are transmitted through the placenta ; such are espe- 
cially syphilis, variola, septicaemia, exceptionally tuberculosis and 
typhoid fever. We shall again refer to these facts in the chapter on 
heredity. 

At the time of birth the individual presents a sufficient resistance to 
the majority of infections : vaccine does not take, eruptive fevers are 
altogether exceptional, also typhoid fever and diphtheria. This immu- 
nity should not, however, be exaggerated; the newborn catches ery- 
sipelas very easily, which localizes itself usually in the navel and is 
almost invariably fatal. 

It is especially during second infancy that infections are frequent. 
It may even be stated that at this epoch of life the tissues are particu- 
larly liable to let the parasites multiply. Pityriasis, for instance, has 
no hold on the aged and is spontaneously cured with the progress of 
years. 

With age, the frequency of infectious diseases diminishes; in the 
old, hardly any but vesical infections and pneumonia occur. One 
might suppose that the immunity of old age depends upon previous 
maladies and insensible vaccinations. The explanation is unsatisfac- 
tory; a certain part must be played by the modifications developed in 
the chemical constitution of the tissues and humours. This view 
is supported by the fact that, when measles prevailed in the Faroe 
Islands, only the old were spared by the disease; in this case, insen- 
sible habituation is out of the question, since the disease was unknown 
up to that time. 

The influence of sex is by no means less interesting. It seems that 
women are for a longer time than men predisposed to the infections 
of childhood. The eruptive fevers, notably varicella, extremely rare 
among men after twenty, are frequently observed among women be- 
tween twenty-five and thirty years of age. 

It is, above all, the different acts of genital life that give feminine 
pathology its peculiar character. Menstruation may be an occasional 
cause of infectious manifestations. Not to speak of herpes, whose 
nature is not well known, erysipelas, in some cases, appears at each 
period. Facts of this kind are seldom observed in hospitals, for men- 
strual erysipelas is benign ; it lasts two or three days and hardly neces- 
sitates a cessation of work; it thus returns for years. Certain women 
may have as many as 50 and 60 relapses. 

Pregnancy may modify the course of certain infections; in some 
cases it impresses them with a character of malignancy (infectious 
jaundice runs its course under the form of grave icterus) ; in other 



GENERAL ETIOLOGY OF INFECTIONS 141 

cases it retards and may even momentarily stop their course. Not 
infrequently tuberculosis seems to stop, and, after confinement, the 
scene changes, the disease assuming a more rapid course. Last of all, 
we hardly need recall the frequency of puerperal infections. In this 
instance, however, the disease presents nothing special; the confined 
woman is in the same situation as a wounded one; it even seems, ac- 
cording to the researches of Straus and Sanchez-Toledo, that the 
uterus of the parturient opposes still a sufficiently strong resistance to 
infectious germs. 

All violations of the laws of hygiene predispose to infections. We 
have already spoken of the noxious effects of great agglomerations. 
In intrenched camps infections are frequent; they are equally so in 
armies in the country. It is always the same diseases that occur: 
scurvy, dysentery, typhus fever. The frequency varies with wars — in 
the Crimea, out of an effective of 309,000 men, 75,000 suffered. 

Crowding in prisons acts in the same way. Not many years ago 
deadly epidemics were of frequent occurrence in hospitals, decimating 
the convalescents ; in the wards devoted to cases of measles, pulmonary 
infections propagated to the despair of physicians. Mortality has 
greatly diminished since isolation has been practised. 

The influence exerted by previous or actual diseases is familiar. 
Some of them predispose to infections : Diabetes favours the develop- 
ment of pyogenesis of the tubercle bacillus; pneumonia, erysipelas, 
rheumatism, far from conferring immunity, predispose to new attacks. 
In most cases infections create a refractory state and prevent future 
attacks. But immunity is never absolute, save, perhaps, in the case of 
syphilis. 

Among causes which intervene to lessen for a moment individual 
resistance, it is well to note fasting and fatigue. 

The influence of fasting is evident ; it is a matter of common obser- 
vation, which has found a scientific confirmation in the experiments of 
Canalis and Morpurgo. 

More interesting is the role of overwork. It has long been recog- 
nised by veterinarians that anthrax and glanders attack specially the 
overworked animals. It was once believed that excess of muscular 
work sufficed to create disease; it is known to-day that it only pre- 
disposes to infection, either by diminishing resistance to surrounding 
germs or by allowing the development of microbes contained in some 
point of the economy. That is what occurs in glanders ; before the fa- 
tigue, the animal supported, without any disturbance, some rare nodes. 

In human medicine examples abound. The fatigues imposed on 
troops lead to the development of various infections, from typhoid 
fever to tuberculosis. Do we not know that students of medicine do 



142 INTRODUCTION TO THE STUDY OF MEDICINE 

not contract the infections to which they are daily exposed, except 
when they are weakened by fatigue or excesses ? The overworking of an 
organ may even explain certain clinical forms. Cerebral rheumatism 
is rare in hospitals, because it occurs only in individuals addicted to 
intellectual activity, in those whose nervous system has suffered from 
late hours, excesses, ambition, and disappointments. Likewise, in 
young subjects, growing bones are predisposed to microbic localiza- 
tions, as expressed by the development of osteomyelitis. Conversely, 
a nonactive organ does not present a rallying point for microbes ; chil- 
dren suffering from mumps do not develop orchitis; this localization 
is not observed until after puberty. 

External agents whose role we have already pointed out may inter- 
vene to favour the development of infections. 

We have already stated that great traumatisms, lacerations, and 
extensive contusions considerably diminish resistance to microbes. 

Inhalation of solid particles, such notably as silica and ferruginous 
dust, may produce small pulmonary erosions favourable to the devel- 
opment of tuberculosis. 

Among physical causes are to be cited, first, cold and heat. The 
action of these two factors is really very complex, and it is not by 
modifying our bodily temperature that they act. The fact that the 
chicken, by nature immune from anthrax, contracts this infection 
when it is exposed to cold, and that, on the contrary, the frog loses 
its immunity when it is heated, is not due to the modifications of the 
organic temperature thus produced in these animals. The immunity 
of the chicken is not due, as some had believed at first, to the fact 
that the bird possesses a temperature too high to permit the develop- 
ment of bacilli, for the pigeon is not endowed with the same power of 
resistance. The frog is refractory to anthrax, not because its tem- 
perature is too low, for the toad contracts the disease. In reality the 
phenomena are more complex; when the chicken is exposed to cold or 
the frog to heat, a whole series of modifications are provoked : nutri- 
tion is disturbed, the life of the cells, and consequently the constitu- 
tion of the humours, is altered, the nervous system, the heart, the leuco- 
cytes are acted upon. The abolition of immunity is the resultant of 
manifold factors. 

It is also through a very complex mechanism that cold or heat 
occasions in man the development of infections. Cold, for instance, does 
not act by subtracting heat, for its influence is at times too quick. It 
is often said that by provoking a cutaneous anaemia it determines a 
visceral congestion, which weakens resistance. This theory is not 
plausible. It is well established to-day that active congestions, far 
from favouring, hinder infections; it is anaemia that diminishes the 



GENERAL ETIOLOGY OF INFECTIONS 143 

means of protection. It is then probable that peripheric cold produces 
pulmonary anaemia, and that the blood is simply driven into the ab- 
dominal vessels; the congestion discovered after an attack of cold is 
already a reactionary phenomenon. 

A good many of the chemical substances, including those known 
as antiseptics, diminish the resistance of the tissues and favour the de- 
velopment of microbes. So the tendency is in surgery to substitute 
more and more asepsis for antisepsis. General intoxications play the 
most important part. Numerous clinical and experimental facts dem- 
onstrate that alcohol, chloroform, and chloral promote the development 
of infections. The inhalation of deleterious gases has a similar effect ; 
it favours general infection or the invasion of the lung. It is well 
known that broncho-pneumonia may be produced by carbonic oxide, as 
pulmonary gangrene by the gas of cesspools. 

In being eliminated through the mucous membranes certain poisons 
destroy the epithelium and open the door to infectious agents. Mer- 
curial stomatitis is due to the development of microbes contained in 
the mouth; hence the conception that it may be cured by means of 
antiseptics, by washing the mouth with the liquor of Van Swieten; 
hence also the possiblity of its being sometimes transmitted 'by con- 
tagion. The microbes of the buccal cavity are exalted to the point of 
overcoming the resistance of the normal tissues. The same mechanism 
presides over the development of mercurial enteritis ; this is also a case 
where mercury, in being thrown off through the intestines, has simply 
facilitated the invasion of the mucous membrane by ordinary bacteria. 

The more we study pathology, the greater we find the intervention 
of microbes in the majority of toxic processes. Hepatic cirrhosis is 
justly attributed to the action of alcohol; but it is possible that the 
poisons act simply by permitting the invasion of the liver by the 
microbes of the intestine; the sclerous process would be, in the last 
analysis, of infectious origin. 

We must recall also that, of the causes already considered as 
favouring infections, not a few act by inducing auto-intoxications; 
diabetes, as well as overwork, are of the number. 

One of the chief causes influencing infection is infection itself: 
there are microbes that invite each other, unite and help one another. 
We thus come to the study of microbic associations. 

Microbic Associations 

Here is, in the first place, an experimental fact which is of a char- 
acter to bring home to you the interest of the process. 

Take a culture of Bacillus prodigiosus — namely, a simple sapro- 
phyte — remarkable only for the beautiful red colour it gives the me- 



144 INTRODUCTION TO THE STUDY OF MEDICINE 

drum in which it develops. Inject a few drops of it heneath the skin 
of a rabbit; no trouble whatever will result. Then take a culture of 
symptomatic anthrax — that is, an anaerobic bacillus which produces 
in certain animals a gaseous gangrene (page 112) ; but the rabbit 
enjoys a natural immunity against this microbe, of which it can receive 
injections with impunity. Here, then, are two bacteria, both harmless 
for the rabbit. 

Take now a third rabbit; inject into it a mixture of the two 
cultures : gaseous gangrene will develop and entail a speedy death. 
Thus, two microbes which, taken separately, are harmless, occasion 
a deadly disease when they are united. In this instance the mi- 
crobe that favours the infection, Bacillus prodigiosus, acts by a 
soluble substance, which glycerine dissolves and alcohol precipitates, 
which resists a temperature of 120°, and, by all these characters, 
resembles peptotoxine. One drop of this injected into the veins 
of a rabbit of 2,000 grammes is sufficient to abolish its natural im- 
munity. 

Many analogous examples might be mentioned. Attenuated cul- 
tures of streptococcus or pneumococcus recover their virulence when 
they are mixed with the soluble products of Bacillus prodigiosus or of 
putrefaction bacteria; in the same way colon bacillus promotes the 
development of the typhoid bacillus. 

So far the results are perfectly concordant; we shall see presently 
some complicated facts. 

Let us take a culture of Bacillus anthracis — namely, of true an- 
thrax, which should not be confounded with the symptomatic anthrax 
above referred to. We are now dealing with a microbe which is equally 
pathogenic both for rabbit and guinea pig. Let us inject into ani- 
mals of these two species a few drops of an anthrax culture mixed with 
a living or sterilized culture of Bacillus prodigiosus. In the guinea 
pig the fatal termination will take place more speedily than if the 
anthrax culture alone had been injected; thus far the outcome is not 
surprising. In the rabbit, the anthrax infection will be thwarted and 
the animal will survive. Thus, the very same microbe, Bacillus pro- 
digiosus, according to the agent with which it is associated and the 
animal which is operated upon, behaves altogether differently. This 
last result leads to a new conclusion: there are some microbes which 
hinder infection. 

These experiments will presently enable us to interpret clinical 
facts. 

Three different microbic associations may be observed in man: (1) 
Two infectious diseases develop side by side without influencing each 
other; (2) in some infections microbic association is the rule and 



GENERAL ETIOLOGY OF INFECTIONS 145 

gives to the clinical tableau its peculiar aspect; (3) the superadded 
infection constitutes a true complication. 

The first eventuality is realized when two eruptive fevers coexist in 
one individual. Measles, scarlet fever, varicella, and smallpox may 
combine without influencing one another; likewise, vaccine and small- 
pox may develop together, as may measles and whooping cough. Each 
disease runs its course on its own account, as if it were alone. 

In other cases one disease starts, the other later follows it. To 
take a simple example, we shall cite vaccinal syphilis. Syphilis and 
vaccine are inoculated simultaneously; the vaccine pustule appears 
first, and when its evolution is over, instead of disappearing, it hard- 
ens and is transformed into a chancre. Likewise, the mixed chancre 
is due to the simultaneous inoculation of the viruses of chancroid and 
syphilis; the soft chancre, whose incubation is shorter, develops with 
its habitual features, and, later, is transformed into a hybrid lesion. 

Cases of pneumo-typhus may also be mentioned. The mixed infec- 
tion begins as a pneumonia; afterward, toward the ninth day, defer- 
vescence takes place, but, instead of being perfect, it is incomplete ; the 
fever changes its type, the typhoid infection, masked until then by the 
pulmonary infection, becomes apparent, and from that moment runs 
its accustomed course. 

Let us now come to the more interesting cases in which two microbes 
unite and constitute what is called, in natural history, a symbiosis. 
Thus, the germs of tetanus and of gaseous gangrene can not, if they 
are isolated, overcome the resistance of healthy tissues; they need the 
assistance of pus cocci, even simple saprophytes. That is just what 
happens when one is wounded by a dirty instrument; if the tetanus 
bacillus and that of gaseous gangrene are present, they will be able 
to develop only by the aid of the various bacteria that accompany 
them. 

Another example is afforded by the study of smallpox. The spe- 
cific agent of this disease is unknown, but it is evident that at a given 
moment the eruptive elements are invaded by pus cocci, markedly by 
staphylococci. The symbiosis is so very intimate that, if the organism 
be modified by a vaccination, the suppuration is cut short; the erup- 
tive elements become crusty and heal, whereas in the nonvaccinated an 
abundant suppuration sets in. The mere fact, therefore, that resist- 
ance against one of the microbes is strengthened has sufficed to hinder 
the development of the other. 

There are diseases in which microbic associations are well-nigh 
constant; they are almost inevitable when the process occupies parts 
largely exposed to the contact of air. In all the infections of the 
mouth the principal microbe is found united to numerous bacteria. 



146 INTRODUCTION TO THE STUDY OF MEDICINE 

Diphtheria, for example, is never pure; in some cases the association 
of microbes plays but a very limited part and has hardly any effect 
on the final result, but none the less it exists. The same is true of the 
infections of the digestive canal: in cholera, typhoid fever, or dysen- 
tery the process is equally complex. Finally, in tuberculosis, at least 
at a certain period, numerous microbes invade the lungs and modify 
the clinical evolution : the tuberculous becomes a pyaemic patient. 

The third eventuality is realized in the very numerous cases where 
a second infection ingrafts itself upon a principal disease; boils, sup- 
purations, parotiditis, gangrenes — observed so often in the course of, 
and especially during convalescence from, grave infections — are due to 
common bacteria which have invaded the organism owing to the weak- 
ening produced by the chief disease. It is even possible that certain 
relapses are in reality only secondary septicaemias and not repetitions 
of the first infections. 

We may cite also the secondary infections of gonorrhoea, notably 
the arthropathies, which are caused by the common pus cocci; the 
pneumonias of erysipelas, which are almost always owing, not to the 
principal agent, but to pneumococcus ; the broncho-pneumonias of 
measles, the nephritis of scarlet fever, the endocarditis, arteritis, and 
phlebitis, which are, in the majority of cases, due to some superadded 
process. 

The secondary infection may sometimes modify the evolution of 
the principal disease to such an extent as to create a clinical form 
altogether special. Such is the case with hemorrhagic smallpox, whose 
very peculiar symptoms are due to an additional septicaemia — namely, 
the intervention of streptococcus. No wonder if vaccination, under 
such conditions, is of little efficacy; it does not insure against the 
secondary infection. 

These few examples, which could easily be multiplied, establish the 
fact that additional infections sometimes impart to the principal 
disease a particular course and a special character of malignancy; 
sometimes they represent simple complications, and sometimes ex- 
plain the development of new manifestations wrongly considered as 
relapses. 

Experimental pathology teaches us that, in some cases, microbic 
associations are able to exert a favourable action. Facts of this kind 
are very rare in human medicine; it is admitted, nevertheless, that in 
the malignant pustule the pus cocci that are found in the lesion 
hinder the development of the anthrax bacillus. 

Erysipelas undoubtedly has sometimes exerted a favourable action ; 
cases are known where, under its influence, lupus, ulcerating and chan- 
crous wounds and tumours, particularly sarcoma, have retroceded and 



GENERAL ETIOLOGY OF INFECTIONS 14? 

healed. These facts have led to the application of inoculation with 
streptococcus, or injection of its toxines, to the treatment of these dis- 
eases. Some encouraging results have been reported. It seems that 
in all these cases the microbe of erysipelas acts by giving rise to an in- 
flammation — that is, by stimulating the slow organic reaction. 

Modes of Entrance of Microbes 

Microbes can penetrate by a great number of ways : First, through 
the shin; and we may well begin by inquiring whether the unbroken 
integument does at all permit the passage of bacteria. As a rule, it 
does not, but there are some exceptions. Anatomists are often at- 
tacked by small pustules, which develop where there is not the slight- 
est abrasion; the liquids of anatomical lacerations swarm with bac- 
teria, which have been able to invade a hair follicle. Garre and Zuck- 
ermann, operating upon themselves, have spread over their skin 
cultures of Staphylococcus aureus ; one of them developed an anthrax, 
the other a boil. Babes has likewise shown that the bacillus of glan- 
ders, incorporated with an ointment, passes through the skin of a 
guinea pig, at least when care is taken to rub the skin in such a man- 
ner as to facilitate penetration into the glands. 

Whether there be any small wound or not, microbes invading the 
skin often give rise to local and innocent manifestations only. Such is 
the case with the anatomical tubercle, which is readily healed by a simple 
curetting followed by iodoformic applications. Other forms of cuta- 
neous tuberculosis, including lupus, may give rise to terrible lesions, 
but, as a rule, scarcely disturb the health. The reason is, the bacillus 
does not find on the skin favourable conditions for development; the 
temperature is not high enough and the tissue is too dense. 

The anthrax bacillus, even in the most susceptible animals, such as 
the guinea pig, often produces nothing more than a curable lesion. 
If a culture is spread on the excised skin, nothing but a little oedema 
results, and that finally passes away. 

If the inoculation is made beneath the skin, the phenomena are 
quite different. Yet it is a fact that adipose tissue does not much 
favour the microbe; so that fat persons resist better than thin ones 
hypodermic injections of viruses. The profounder the inoculation, 
the greater are the chances for the infection to develop. The example 
of hydrophobia is, in this respect, altogether demonstrative. 

The mucous membranes, even when healthy, are more easily pene- 
trated by microbes than the skin. The tubercle bacilli can pass 
through the conjunctiva, the bronchial or intestinal mucous mem- 
brane, without leaving any trace of their passage; they proceed to 
locate themselves in the corresponding ganglia, in the neighbouring 



148 INTRODUCTION TO THE STUDY OF MEDICINE 

serous membranes, and excite specific manifestations which can not be 
traced to their origin. In other instances reactionary lesions break 
forth; pneumonia is the expression of the effort the organism makes 
for preventing the passage of the pneumococcus. 

Ingestion appears to be a less certain method of infection than 
inhalation. It is nevertheless through the alimentary canal that in- 
fection takes place in typhoid fever, in dysentery, or cholera, and some- 
times, especially with children, in tuberculosis. Hence arises the 
question whether the meat of infected animals is fit for consumption. 
To-day this question may confidently be answered : When there is gen- 
eralized infection, as in cases of anthrax and glanders, the seizure of 
the meat should be ordered. As regards tuberculosis, which is ob- 
served in 3.8 per cent of cattle slaughtered at Villette, the use of the 
meat is allowed when the lesions are local. 

It has been asserted also that milk propagates tubercular infection; 
but this liquid contains no bacilli unless the mammary glands are 
affected or the infection is extensive; therefore milk seems to be 
less dangerous than had at first been thought; and is the less so as it 
is mixed with noncontaminated milk, for the dilution of the virus 
diminishes the chances of contagion. 

Infection by the genito-urinary passages, if we except venereal 
diseases, such as gonorrhoea, syphilis, and soft chancre, is quite rare. 
Under normal conditions, microbes do not go beyond the navicular 
fossa in men. In women they are very abundant in the vulva and 
vagina. But when pathogenic agents, such as streptococcus, are intro- 
duced into this canal, the germicidal liquids secreted by the mucous 
membrane destroy all the germs within forty-eight hours (Menge). At 
the time of confinement the resistance of the genital organs grows still 
stronger. Straus and Sanchez-Toledo established that the anthrax 
bacillus, introduced into the vaginal canal of a female guinea pig 
having just brought forth little ones, produces no trouble whatever 
in this animal, by nature so sensitive to anthrax. In the human 
species resistance is as well marked, for puerperal fever is, on the 
whole, quite rare; it is altogether exceptional in the country, notwith- 
standing the fact that the parturients take very few antiseptic pre- 
cautions. 

The serous membranes represent another entrance, open at times to 
infection; but despite oft-repeated assertions to the contrary, they are 
very well defended. Hence the possibility of great surgical operations ; 
for, in spite of all the precautions taken, morbid germs are always 
introduced; they are constantly found beneath the dressings. They 
are, however, in too small numbers to overcome the resistance of the 
organism. 



GENERAL ETIOLOGY OF INFECTIONS 149 

Lastly, another passage for infection is the nervous system; the 
agent of hydrophobia propagates through the nerves, as has been 
admitted by Duboue, of Pan, on the basis of clinical experience, and 
as numerous experimental researches have demonstrated. 

In this manner the virus reaches the nerve centres; therefore, the 
nearer the affected nerve is to the bulb, the shorter the period of incu- 
bation; and furthermore, the first manifestations will vary with the 
region primarily contaminated. 

Protection of the Organism against Microbes 

When microbes have passed the first barrier, and been introduced at 
some point of the economy, they will multiply and secrete injurious 
substances. 

Then three results are possible. 

1. The microbe is not virulent, the leucocytes rush up and soon 
destroy it. Sometimes spores persist for a certain time, as when Ba- 
cillus subtilis is injected, but they produce no disturbance. 

2. If the microbe has a pathogenic action, a struggle is entered 
into at the point where the invasion is made; liquids are exuded, leu- 
cocytes come out of the blood vessels; a local lesion is formed which 
will endeavour to circumscribe the infection. 

3. Lastly, when the microbe is very virulent, the organism is, as it 
were, struck with impotence; the cells which attempt to approach the 
pathogenic agent are repelled by secretions credited with a power 
called negative chemiotaxis ; the local lesion is wanting ; general infec- 
tion is produced. 

Whether or not a local lesion be created, the microbes penetrate 
always beyond their point of entrance, following either the lymphatic 
or the venous path. 

If they get into the lymphatic vessels, they meet with ganglia 
which can stay their course. The function of these little organs is 
revealed by some experimental researches and numerous clinical obser- 
vations. 

In the course of the most diverse infections — acute, subacute, or 
chronic inflammations, suppurations, as well as anthrax, tuberculosis, 
or syphilis — we observe the swelling of the ganglia corresponding to the 
affected regions. Modifications take place in them, analogous to those 
occurring at the point of inoculation; the cells rapidly multiply, and, 
in acute cases, a very extensive periganglionic exudation is sometimes 
produced. 

The lymphatic glands, especially in regions where they form 
chains, represent veritable fortresses which stop, finally or temporarily, 
the pathogenic agents. 



150 INTRODUCTION TO THE STUDY OF MEDICINE 

The other lymphoid productions play a similar part. The fact is 
demonstrated with respect to the tonsils; it is equally certain for the 
closed follicles, isolated or agminate, that are found at the surface of 
our mucous membranes. 

This conception can even be extended to the serous membranes. 
Anatomists have described in these membranes formations which, by 
their arrangement and structure, represent ganglia flattened out, as it 
were. Such an organ is, for instance, the great omentum. Direct ex- 
periment demonstrates the protective role of this membrane. To be 
convinced of this, extirpate the omentum in rabbits and guinea pigs. 
Later, after a period of a month or two, inject into the abdominal cav- 
ity of the animals thus operated upon a few drops of a virulent culture 
of Staphylococcus aureus ; death supervenes in twenty-four hours, or at 
the latest within two or three days. Controls of the same weight, who, 
to make the conditions identical, have been subjected to a simple lapa- 
rotomy, receive the same amount of culture and all survive. 

It should not be concluded, however, that the suppression of the 
great omentum entirely destroys the resistance of the peritoneum. 
For the animals operated upon survive if they receive a very small 
dose of a virulent culture, or if an attenuated microbe be employed. 
In repeating the inoculation, however, we notice that the animal de- 
prived of the omentum is growing thin and cachectic, and finally suc- 
cumbs, while the control animals manifest no disturbance whatever. 

The role of the omentum must be especially marked in the young, 
because, with years, a fatty infiltration occurs that diminishes its 
activity. It is, however, in children that the peritoneum is frequently 
threatened by microbes, which swarm in the gastrointestinal canal, and 
so often cause inflammations there. 

Similar protective arrangements are likely to be met with in the 
other serous membranes; but no experiments have been undertaken on 
the subject. 

Microbes invade the blood, either after having passed through the 
lymphatic glands or by directly penetrating into the capillaries or 
veins. If they enter by way of the stomach or intestines, they reach 
the portal vein and successively pass through the liver, right heart, 
lungs, and left heart, to be thrown thence into the general circulation. 
In all other cases they pass first through the lungs. 

No matter by what way they enter, the microbes that have reached 
the general circulation rapidly disappear from the principal vessels; 
at the end of ten or fifteen minutes they are no longer found in them, 
even when intravenous inoculation has been practised on the animal. 
The blood then represents an inhospitable medium for bacteria, which 
must abandon it and take refuge in the capillaries of the organs. 



GENERAL ETIOLOGY OP INFECTIONS 151 

Here the battle between the organism and the pathogenic agents is 
fought out; the latter begin to multiply and secrete toxic substances, 
which should insure them victory, while the cells of the body en- 
deavour to exert their protective role, either by manufacturing germi- 
cidal or antitoxic products, or by picking up and digesting the 
microbes. 

Two hypotheses are possible. It may be assumed that the various 
phases of the struggle are alike in all the capillaries ; in which struggle, 
as the case may be, the microbe or the organism would triumph, and 
the ultimate result would be the sum of the partial results of the same 
character. Or it may be supposed that the phenomena vary from one 
capillary network to another; that the effects of the struggle are not 
the same in all the organs, but in some of them the microbe is victori- 
ous, in others the cell. If so, the phenomena become more complex; 
the final result will be the sum of the partial results of the different 
kinds. 

These theoretical considerations lead to the question whether there 
do not occur differences in the evolution of infectious diseases accord- 
ing to the vessel by which the culture is introduced. 

Protective Role of the Organs. — In most cases the experimenters 
inject the microbes through some peripheral vein; then the pathogenic 
agent first passes through the capillaries of the lung, to reach after- 
ward the general circulation. In order to bring out clearly the role of 
the pulmonary capillaries, an injection must be made at the very 
origin of the aorta; for this, it suffices to introduce a cannula by the 
central end of the right common carotid. The differences which will 
be presented by the development of the disease in the two cases will 
enable us to appreciate the function of the lung. 

In other experiments the injection will be made by a branch of the 
portal vein to ascertain the action of the liver; by the distal end of 
the carotid artery to study the influence of the brain; by the femoral 
artery to notice what occurs in the less highly organized tissues. 

The results vary with the microbes employed. 

With anthrax cultures the animals inoculated by the aorta suc- 
cumb first; those injected through the peripheral veins survive a little 
longer, which indicates a slight action on the part of the lungs. But 
this protection is of little importance and vanishes when the virus 
is very active. Lastly, the injections made by the carotid allow a sur- 
vival somewhat longer than the intravenous inoculations. Thus far 
the differences are not considerable : if some animals resist longer than 
others, all succumb ultimately. 

Altogether different are the results when the anthrax passes 

through the liver; thus, out of twelve animals having received con- 
11 



152 INTRODUCTION TO THE STUDY OF MEDICINE 

siderable doses of anthrax culture by the portal vein, only three have 
succumbed. The liver, then, has the property of arresting and killing 
the anthrax bacteria; it plays a very important part in the protection 
of the organism against anthrax infection. With a very virulent cul- 
ture, a dose of half a cubic millimetre injected through a peripheral 
vein kills a rabbit of 2 kilogrammes in thirty-eight hours. A dose of 8 
cubic millimetres introduced through a portal vessel is incapable of 
killing a somewhat smaller rabbit. That is to say, a quantity of an- 
thrax bacilli 64 times that which is fatal by the peripheral veins is 
completely annihilated by the liver. 

The protective action of the liver, which is so conclusively shown 
by these experiments made with the anthrax bacillus, is just as easy 
to demonstrate with the Staphylococcus aureus. 

Let us take a virulent sample, and, after diluting it in bouillon, 
inject it, as we did anthrax, through five different vessels. Contrary 
to the preceding results, the animals inoculated through the distal 
end of the carotid artery succumb first ; the brain therefore represents 
an excellent medium of culture for staphylococcus. Next, the animals 
injected through the aorta or femoral artery perish. Those that have 
received the virus through peripheral veins survive longer; those that 
have received it by the portal vein resist inoculation. However, the 
liver acts with less energy upon staphylococcus than upon the anthrax 
bacillus; it neutralizes 8 fatal doses, instead of 64. 

If we now pass to streptococcus, we find quite different results. 
The liver has no longer any power of protection; the microbes find in 
its parenchyma excellent conditions for vegetation, and animals in- 
jected through the portal vein are generally the first to succumb. A 
little later die those that have been inoculated through the aorta, the 
carotid, or the femoral artery. As to animals injected through the 
peripheral veins, they die slowly, or, if the virus be not a very active 
one, they may survive. 

The lung then represents a protective organ against streptococcus; 
it fulfils a role analogous to that exercised by the liver against Ba- 
cillus anthracis or Staphylococcus aureus, except that it destroys 
pathogenic agents with less energy; the lung hardly neutralizes more 
than one deadly dose. 

With colon bacillus the results are very variable. Experimenting 
with a microbe drawn from dysenteric stools, we have found a mani- 
fest action of the liver. On the contrary, in previous researches, pur- 
sued with another sample, the animals inoculated by the portal vein 
or the carotid artery succumbed first. The liver, far from destroying 
this microbe, affords it an excellent medium of culture. This result, 
while very deceiving from a teleological point of view, accounts well' 



GENERAL ETIOLOGY OF INFECTIONS 153 

for the frequency and gravity of hepatic infections of gastrointestinal 
origin. 

With the bacillus of dysenteriform enteritis, the results vary with 
the age of the culture. If the culture is recent — viz., if it is four or five 
hours old — it does not yet contain any toxines ; the liver then exercises 
a protective role: it arrests and destroys the microbe. If the culture 
is several days old, toxines have been produced in abundance; they 
annihilate the action of the liver and alter this gland; consequently 
the animals inoculated through the portal vein succumb first. Thus 
the liver acts upon the bacillus ; it destroys the figurate element, but 
has no action upon its products of secretion. 

Similar differences are observed in studying parasites of a higher 
order. Thus with cultures of Oidium albicans, the animals injected 
through the carotid perish first. The lung retards very slightly the 
course of the infection. The liver and kidneys arrest great numbers 
of the parasites and prevent the extension of the process; they pro- 
tect the economy very efficiently. 

The various results above indicated are summed up in the accom- 
panying tabular representation (page 154), showing in what order 
the animals succumb, according to the mode of introduction of the 
microbes. 

In brief, microbes injected in a blood vessel stop, in great num- 
bers, within the first capillary plexus they enter. This is perhaps but 
a mechanical phenomenon of molecular adhesion comparable to that 
which, in a porcelain filter, prevents the bacteria from passing through 
pores larger than themselves. It may be, however, that a vital process 
is called into play, an action of arrest exercised by the endothelium, 
for analogous phenomena occur when, instead of figurate elements, sol- 
uble substances are introduced ; injections made through different parts 
of the vascular system prove equally well the action of the organs both 
on poisons and on microbes. 

In both cases the most important role is that played by the liver. 
The action of this gland, however, is not exercised indiscriminately 
upon all the substances or all the bacteria that reach it; there are 
poisons which the liver retains and transforms, others which it allows 
to pass, and still others which seem to acquire in its interior an in- 
crease of activity. This is at least what results from the experiments 
of Teissier and Gruinard on the diphtheria toxine. 

For microbes the results are the same : some stay there and perish, 
such as Bacillus anthracis, the staphylococcus, the bacillus of choleri- 
form enteritis, the oidium; others, as the streptococcus and colon 
bacillus, easily develop there and grow stronger. 

The action of the liver is more marked on microbes than on poi- 



154 



INTRODUCTION TO THE STUDY OF MEDICINE 



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GENERAL ETIOLOGY OF INFECTIONS 155 

sons. When a toxic alkaloid is injected through a portal branch, the 
animal experimented upon is killed, provided the dose introduced be 
double that which is fatal by way of peripheral veins. As to microbes, 
we have seen that the liver arrests 64 fatal doses of anthrax and 8 
fatal doses of staphylococcus. Its action is then much more important, 
or at least more marked, in infections than intoxications. 

Furthermore, experiments demonstrate that other organs may also 
serve to protect the organism against infections. Such is the lung, 
which acts in a certain measure on the bacteridia of symptomatic an- 
thrax and upon the staphylococcus, and exerts an action still more 
efficacious upon the streptococcus. Moreover, the kidney can retain 
the oidium and prevent the dissemination of this parasite. 

We see, furthermore, from the experiments above reported, that 
blood is not a hospitable medium for microbes ; the few which succeed 
in passing through the first capillary network do not circulate long; 
they lodge in the various organs, so that in a few minutes the blood 
again becomes sterilized. 

The localization of bacteria is controlled by the following three 
conditions : The mode of entrance, of which we have sufficiently shown 
the importance; the physiological and pathological conditions of the 
organs, of which we shall presently say a few words. 

The Causes which Explain Microbic Localizations 

Bacteria which have passed through the capillaries of the first 
organ encountered, and which circulate for a moment in the blood, 
have a great tendency to settle in parts endowed with a strong nutri- 
tive or functional activity. In the young they stop in the growing 
bones; but they always spare those organs, such as the testicles and 
ovaries, which have not yet entered upon active life. In the case of an 
individual who has overtired an organ — the brain, for example — the 
localization will take place in that organ. 

It is possible to fix at will the microbes in this or that part of the 
organism by producing traumatic or other lesions; by weakening the 
resistance of a tissue we favour its colonization by pathogenic agents. 
We have already mentioned the well-known experiment of Max Schul- 
ler : a traumatism at the knee of a guinea pig is followed by the devel- 
opment of a white swelling (tumeur blanche) if, at the same time, 
tuberculosis be inoculated. Clinics abound in similar examples. 
Parents always trace the beginning of a coxalgia, a tubercular menin- 
gitis, or a Pott's disease to a blow received by their child or to a fall. 
The observation is often just; but the blow or the fall is not respon- 
sible for the lesion; it has only favoured the development and local- 
ization of tubercle bacilli, which were already present in the organism. 



156 INTRODUCTION TO THE STUDY OF MEDICINE 

When microbes are localized in an organ or tissue, the struggle 
begins. The final result will depend upon the forces of each of the 
two parties present. It is readily understood that all causes disturb- 
ing the state of health — various mechanical, physical, chemical, or ani- 
mate agents ; bad nourishment, fasting, overwork, excesses — in a word, 
all the conditions which we have found to be favourable for the devel- 
opment of infections, are also those that will render their evolution 
more serious. 

In the case of microbes, we must first consider their number. It 
is altogether exceptional that a single microbe should be able to pro- 
duce a disease, though the case may be realized with extremely virulent 
anthrax cultures : one bacteridium kills a young guinea pig. In most 
cases, to overcome the resistance of the organism, large numbers of 
microbes are required. Thus the guinea pig, of all animals the most 
susceptible to tuberculosis, does not catch the infection unless 820 
bacilli are introduced beneath its skin. This figure may already seem 
quite considerable; but with the pyogenics the required numbers are 
much greater. 

Operating with Proteus vulgaris, Watson Cheyne states that 
5,000,000 to 6,000,000 microbes injected beneath the skin do not 
produce any lesion; 8,000,000 cause the formation of an abscess; 
56,000,000 give rise to a phlegmon, to which the animal succumbs 
within five or six weeks; to cause death within twenty-four or thirty 
hours, 225,000,000 must be injected. 

The same author has studied the action of the staphylococcus upon 
the rabbit: for producing an abscess, 250,000,000 microbes are re- 
quired; for causing death, one milliard (1,000,000,000) is the requisite 
number. 

In all these experiments the microbes were injected beneath the 
skin. By varying the mode of entrance, different results are obtained. 
To occasion suppuration by Staphylococcus aureus, it has been neces- 
sary, in the researches of Herman, to inject 4 to 5.3 centimetres of the 
culture into the peritoneum, 0.75 to 1 beneath the skin, 0.25 into the 
pleura or arachnoid, 0.05 into the veins, 0.0001 into the anterior cham- 
ber of the eye. The anterior chamber is then the least protected 
part of the organism. The same is demonstrated also by the study 
of symptomatic anthrax; this virus, harmless for the rabbit when in- 
jected hypodermically, causes speedy death when introduced into this 
part of the eye. 

The figures given by the authors have of course but a relative 
value; for virulence differs much with different samples and its vari- 
ations constitute undoubtedly the most important factor that we have 
to study. 



GENERAL ETIOLOGY OF INFECTIONS 157 

Microbes become attenuated when they are kept outside of the 
organism. In our artificial cultures they rapidly lose their virulence. 
We can even hasten their attenuation by placing them in unfavour- 
able media. By maintaining the culture at too high a temperature, by 
subjecting it to the action of compressed oxygen, by adding to the 
medium antiseptic substances, we can reduce its pathogenic power pro- 
gressively. 

To increase the virulence, we must reverse the conditions — make 
inoculations in animals, cultivate the microbe in favourable media, 
above all in bouillon to which some blood serum or liquid of ascites 
is added. The procedure of inoculations in series, already employed 
by Davaine, has enabled this scientist to obtain a virus sufficiently 
active to kill guinea pigs into which one millionth of a drop was in- 
jected. Similar facts are observed in clinics. One of the parasites 
which we carry, pneumococcus, for example, when exalted, gives rise 
to pneumonia; it then can by contagion infect a second person, and, 
thus transmitted, produce a little epidemic. Let us note, however, that 
a microbe exalted for one animal species is not necessarily so for oth- 
ers; every day we see streptococci having caused mortal diseases in 
man prove hardly pathogenic at all for animals. We have studied a 
sample of anthrax which, after successive passages in rabbits, had 
become, contrary to the rule, far more virulent for this animal than 
for the guinea pig. 



CHAPTER IX 
GENERAL PATHOGENESIS OF THE INFECTIOUS DISEASES 

The mode of action of microbes upon the animal organism — Importance of microbic 
toxines — Putrid poisons — Poisons produced by pathogenic bacteria — Principal 
bacterial toxines — Toxines produced by nonbacterial infectious agents — Mode 
of action of toxines : reactions excited by them. 

In order to understand in what manner microbes accomplish in- 
jury to the organism, three principal hypotheses have been advanced. 

The first, which no longer has any but an historical interest, as- 
sumed that an obstruction of the capillaries by bacteria occurred. It 
was a mechanical theory. 

Secondly, a struggle for life was assumed. It was held by those 
entertaining this view that the microbes and cells vied with each other 
over the alimentary materials carried by the blood and lymph. Which- 
ever of the two elements succeeded in appropriating the most, reduced 
the other to starvation. 

The third and modern conception seems to be established in 
indisputable proofs, and regards the infectious process as an intoxica- 
tion. According to this view, the microbes act through the agency 
of the soluble substances which they contain or elaborate. 

Putrid Poisons - 

Before the pathogenic microbes were known — i. e., at an epoch 
when the animate nature of putrefactive agents was not even sus- 
pected — important results had already been obtained. 

In 1758, Seybert demonstrated that the putrefaction of pus, serum, 
and infusions of meat developed in these fluids a high degree of patho- 
genicity. At the beginning of the present century the remarkable 
researches of Gaspard, completed by Magendie, Virchow, Stich, and 
especially by Panum, conclusively established the existence of putrid 
poisons. 

The substances originating in the course of putrefactions are very 
great in number. Gases, fatty acids, aromatic substances, and amido 
158 



GENERAL PATHOGENESIS OP THE INFECTIOUS DISEASES 159 

bodies are encountered, which, however, are not sufficiently numerous 
or active to be taken into account. Next, we meet with albuminoid 
substances and bases analogous to vegetable alkaloids. Panum ad- 
mitted that putrid poison was of an albuminoid nature; on the other 
hand, most authorities held a contrary view, and their opinions seemed 
to be definitely established by the results obtained through the re- 
searches of Gautier, Selmi, and Brieger. The putrefactive bases were 
called ptomaines (Selmi), or, what was etymologically more correct 
(7rTw/x,a, 7TT(o/>taTo?, cadaver), ptomatines (Kobert). 

A great number of cadaveric bases are now known. 

Some of these substances are chemically well defined : methylamine, 
trimethylamine, triethylamine, propyl, butyl, amylamine, neuridine, 
saprine, cadaverine, putrescine, neurine, choline, gadinine, collidine, 
etc. Others are distinguished by their toxicity, and are sometimes 
named according to the analogy of their action with that of certain 
alkaloids — e. g., mydaleine, ptomatropine, ptomatomuscarine, ptoma- 
tocurarine, ptomatoconicine, ptomatoveratrine, tyrotoxine, etc. 

Ptomaines differ notably according to the time at which the prod- 
ucts of putrefaction are studied. Some appear and later disappear, 
to be replaced by others. The chemical researches which have made us 
acquainted with these results, however interesting they may be, should 
have been completed by bacteriological researches. It is a question 
whether these different ptomaines are produced at the various phases of 
life of the same microbes, or whether their successive appearance and 
disappearance depend upon different microbes, which destroy or trans- 
form the substances already produced by their predecessors. 

Even though we do not exactly understand the role of ferments 
in the genesis of ptomaines, we are better acquainted with the part 
played by the media in which they are produced. We know that cer- 
tain bases are encountered in all putrefactions — for example, neuridine. 
On the contrary, neurine is found only in the putrefaction of the flesh 
of mammalia, and muscarine only in the putrefaction of the flesh of 
fish. Similarly, it is at the expense of fish that gadinine, ethylendia- 
mine, and trimethylamine are formed. Dimethylamine has so far been 
found only in the putrefaction of gelatine or of yeast. Tyrotoxine is 
the poison which is formed in decomposed milk and cheese. 

Drs. Kostiurine and Krainsky very justly remark that the toxicity 
of the products of putrefaction is in direct ratio to the chemical 
complexity of the matters undergoing putrefaction — e. g., more poison 
is yielded by meat than by bouillon, and more by bouillon than by 
saline solutions, indeed, the latter not yielding any. 

Thus far all the results seem to harmonize and to lead to the 
admission that the putrid poisons are of alkaloidal nature. There has 



160 INTRODUCTION TO THE STUDY OF MEDICINE 

been some question, however, whether this conclusion was justified. 
Chemists have been reproached with having created, as it were, the 
substances they isolate, or at least with having dissociated the true 
toxic molecule, which is more complex and unstable. The ptomaine, 
it is objected, does not pre-exist in the putrid liquid ; it enters into the 
constitution of a proteid substance, from which it is driven by analyt- 
ical procedures. The true poison, therefore, is an albuminoid. In 
favour of this view may be mentioned a great number of researches 
demonstrating that when putrid matters are treated with alcohol the 
substances precipitated by this solvent are the most toxic. The ques- 
tion, therefore, is deserving of further investigation, which would 
probably lead to the discovery in putrid matters of toxines, some be- 
longing to the group of toxalbumins and others to the peptotoxines 
and toxalbumoses. 

Poisons produced by Pathogenic Bacteria 

The putrid poisons are of great interest, not only because some 
are constantly formed in the digestive canal, as has already been 
stated, but also on account of the fact that their study is a suitable 
introduction to the history of the poisons produced by pathogenic 
micro-organisms. 

Davaine thought that the anthrax bacillus secreted a substance 
which agglutinated the red blood corpuscles, and Pasteur confirmed 
this hypothesis in studying the effects of filtered anthrax blood. Tous- 
saint, Chaveau, and especially Gautier, argued in favour of toxic secre- 
tions of bacteria. Pasteur finally offered a basis of demonstration by 
establishing the fact that filtered cultures of the bacillus of chicken 
cholera produced transitory somnolency in birds — i. e., it reproduced 
one of the symptoms of the disease. This symptom, however, was of no 
particular interest, and Pasteur therefore refrained from concluding 
that the microbe acted by toxines. 

The idea of a microbic intoxication was, however, fully accepted 
when it was demonstrated that infectious agents are capable of pro- 
voking a fatal disease even though they remain localized at some point 
of the organism. Loeffier sustained this hypothesis with reference to 
diphtheria; Koch accepted it as regards cholera, and there was no 
logical escape from its adoption with regard to tetanus, symptomatic 
anthrax, and emphysematous gangrene. 

Then Brieger, prepared as he was by his studies upon ptomaines and 
putrefaction, extended his researches to pathogenic microbes. In the 
impure cultures of tetanus bacillus with which he worked, and in 
those of typhoid bacillus, he found various ptomaines which he studied 
from the standpoint of chemistry and toxicology. From that moment 



GENERAL PATHOGENESIS OF THE INFECTIOUS DISEASES 161 

the way was open. Investigators hastened to engage in research and 
described a great number of toxic bases of microbic origin. 

Serious objections, however, were soon raised. It was pointed out 
that the ptomaines as extracted from cultures are far less powerful 
than the total cultures, and fail to produce the same phenomena. Pur- 
suing the study of microbic poisons, it was recognised that the most 
active substances, as in the case of putrid poisons, are not soluble in 
alcohol, but precipitated by it. The tendency was then to attribute 
the toxicity of cultures to substances considered successively as fer- 
ments, peptones, albumoses, toxalbumins, globulines, proteines, nucleo- 
albumins, etc. 

The idea of comparing the microbic toxines with ferments is based 
on chemical and toxicological facts. Like ferments, (a) toxines are 
precipitated by alcohol; (b) adhere to precipitates of calcium phos- 
phate which are produced in the liquids containing them; (c) are 
destroyed by heat; (d) they act in infinitesimal doses. This compari- 
son is acceptable, especially at the present day when there is a tend- 
ency to consider the fermentative power as a physical property of mat- 
ter; the albuminoid substance serves simply as the substratum of a 
mode of energ}' - . That it may be deprived of its power by means of 
various procedures, notably by heating, is quite conceivable. The con- 
ditions would be the same as in the case of a magnet. The magnetic 
property is one of a physical order; the magnetized iron has no special 
chemical constitution. With this conception the ferment is a complex 
material which has received from the living substance a certain 
degree of energy, possessing, as it were, a part of vital activity. It 
is said by Buchner to be a semiliving substance. At any rate, it is the 
highest expression of matter destitute of life. Thus understood, 
the action of toxines is no more mysterious than that of ordinary 
ferments. 

What render the study of microbic toxines more difficult are the 
varying results obtained according to a great variety of circumstances, 
in but few of which precision is possible. 

The action varies with the same microbe according to different 
samples. As a rule, it increases as the virulence becomes greater. 

The effects are modified in the same sample according to the cul- 
ture medium. The more complex the medium, the greater the amount 
of toxines produced. In this respect nothing is as good as the natural 
organic fluids, such as blood serum and ascitic fluid, under which con- 
ditions virulence is best preserved. 

In the same culture toxicity varies with age — i. e., with the time 
elapsing since the inoculation. Very often it increases steadily with 
age; in other instances the reverse is true. No definite rules can be 



162 INTRODUCTION TO THE STUDY OF MEDICINE 

formulated in this respect any more than with reference to the action 
of heat or air. The diphtheria bacillus, for example, produces more 
poison in well-aerated bouillon, while the reverse is true of the strepto- 
coccus. 

The variability of the results depends partly upon the plurality of 
toxines. In fact, there are toxic substances which exist in the bodies 
of bacteria. These are the proteines or nucleo-albumins, which are dif- 
fused in the medium when the culture grows old — namely, when the 
microbes are destroyed and disintegrated. On the other hand, the 
medium contains substances which are in part due to a secretion of the 
bacteria themselves. Others are formed either by destruction of nutri- 
tive materials or by synthesis. These are the toxalbumins, the toxal- 
bumoses, and the toxopeptones. As to the ptomaines, they are grad- 
ually being recognised as derivatives of true toxines. 

When introduced into a living organism, toxines do not at first 
produce any disorder. A period of latency elapses, varying from a 
few hours to several days, before the appearance of morbid phenomena. 
On the other hand, with the poisons derived from true toxines — for 
example, the ptomaines — the manifestations are of immediate occur- 
rence, exactly as is the case when a vegetable alkaloid is injected. It 
has therefore been supposed that the primary poison is decomposed in 
the organism and parts with its toxic radical. This hypothesis is 
apparently quite plausible, since alkaloids are found in the urine; at 
any rate, substances which have an immediate action are detected 
there. However, this conception should not be admitted in all its sim- 
plicity, for the phenomena are probably more complicated, and the 
total toxine has perhaps already caused profound modifications in the 
organism. 

In general, it is difficult to say what are the phenomena provoked 
by toxines. The manifestations evidently vary from case to case. 
However, the events may be divided into three groups : 

(a) Some are seen at the point of introduction of the substance; 
these are the local manifestations. 

(b) Others express the impregnation of the entire economy; these 
are the general manifestations. 

(c) Finally, others point to a selective action on certain organs, 
apparatus, or tissues. 

Toxines may provoke at the point of introduction a lesion similar 
to that produced by the agent from which they are derived. First an 
inflammatory oedema is produced. For example, the erysipelas poison, 
like the living streptococcus, produces oedema in man as well as in 
animals — a fact convincingly manifested in subjects into whom steril- 
ized cultures of streptococcus were injected for therapeutic purposes. 



GENERAL PATHOGENESIS OF THE INFECTIOUS DISEASES 163 

Next, we have the suppuration so easily produced by the soluble prod- 
ucts of the streptococcus, staphylococcus, and gonococcus. Dr. Christ- 
mas injected into a normal urethra a trace of gonococcus toxine and 
produced a purulent discharge, which, however, disappeared within a 
few hours, as he did not continue to deposit the irritating substance on 
the mucous membrane. 

Likewise, the necrosis characterizing gangrene is induced by sol- 
uble products, as is proved by subcutaneous injections of toxines de- 
rived from the bacillus of emphysematous gangrene. The same is true 
of pseudo-diphtheritic membranes, which may be produced by intro- 
ducing into the trachea a few drops of the toxine generated by the 
Loeffler bacillus. 

In this manner all the local processes attributable to microbes can 
be reproduced by means of the toxines freed of the living germs. The 
general phenomena are due to the same mechanism. The injection 
of soluble products gives rise to fever with all its consequences — 
e. g., variations in combustion, respiration, and urinary secretion. 
When sterilized cultures of streptococcus are injected into man for 
therapeutic purposes, fever results, ushered in by chills and attended 
by general depression, dry tongue, and, in some cases, an often abun- 
dant outbreak of herpes labialis. 

The introduction of strong doses or repeated injections of toxines 
give rise to cachexia similar to that induced by prolonged infectious 
processes. Diarrhoea sets in, the cells of the organs degenerate, and 
death ensues from marasmus. In this respect the toxines of the tuber- 
cle bacillus are very interesting; they act like the microbe from which 
they are derived. 

If the course is slower, the manifestations may predominate in 
a viscus, thus constituting an affection which sometimes begins, and 
in most cases continues, long after the toxine injections have been 
suspended. In this way it is possible to reproduce visceral sclerosis, 
hepatic cirrhosis, nephritis, myocarditis, as well as paralysis and mus- 
cular atrophies often due to medullary lesions, predominating in the 
large cells of the anterior horns. 

Thus, toxines can reproduce all the lesions induced by microbes. 
We may, therefore, conclude that infection is but a chapter of intox- 
ications. 

Since microbes give rise to toxic substances during the course of 
diseases which they originate, some authorities have entertained the 
idea of searching for these poisons in the organism of the sick. The 
labours of Eumo and Bordoni have established their presence in the 
blood; Professor Bouchard's experiments have demonstrated their pas- 
sage into the urine. It should be remarked, however, that the phe- 



164 INTRODUCTION TO THE STUDY OF MEDICINE 

nomena are in reality very complex. In an infected organism three 
kinds of poison are encountered : 

(a) The microbic toxines, engendered by the pathogenic agent. 

(b) The putrid poisons, originating in the intestine, where fer- 
mentations are often more intense than normally. 

(c) The cellular poisons, due to disturbance of assimilation, which 
is exaggerated and vitiated. 

If, in addition, the organs destructive to toxines are altered and 
incapable of fulfilling their role, which is often the case, we can under- 
stand how the sources of intoxication are multiplied. If the organism 
resists, it is owing to the fact that part of the toxiues constantly 
escapes through the emunctories, notably by the kidneys; the urine 
becomes hypertoxic, and this hypertoxicity is a safeguard for the econ- 
omy. In many cases, however, there is a greater complexity of phe- 
nomena. In pneumonia, for instance, the urinary toxicity grows less 
as the disease progresses ; the poisons accumulate in the organism, to 
be suddenly thrown out at the moment of defervescence; a urinary 
crisis is then observed, characterized by a strong polyuria and a tox- 
icity of the urine, which may exceed from five to six times the normal 
toxicity. 

The Principal Bacterial Toxines 

Not wishing to describe the microbic toxines thus far studied, 
we believe that it would be interesting to sum up in a few lines our 
present knowledge of the principal toxines. 

We must first consider those infections whose mechanism is inex- 
plicable otherwise than by admitting the action of a soluble poison. 
We here refer to those infections whose agent remains at the point of 
inoculation — e. g., diphtheria, tetanus, cholera, emphysematous gan- 
grene, and symptomatic anthrax. 

Diphtheria. — The diphtheritic toxine, discovered by Eoux and 
Yersin, can be obtained in such high degree of activity that -^ and 
even -g--^ of a cubic centimetre kills a guinea pig of 500 grammes 
weight. If we remember that 1 cubic centimetre of the fluid gives 1 
centigramme (0.01) of dry residue, say 0.0004 of organic matter, and 
that the toxine represents but one part of this matter, we are led to 
the conclusion that it can poison a living being 20,000,000 times 
greater than its own weight ! 

The active principle, insoluble in alcohol, is destroyed by light, 
heat, oxidizing agents, iodine water, and trichloride of iodine. Eoux 
and Yersin hold it to be a ferment; Brieger and Fraenkel, a toxalbu- 
min; Wassermann and Proskauer, an albumose, or, at least, intimately 
united with an albumose. 



GENERAL PATHOGENESIS OF THE INFECTIOUS DISEASES 165 

All living beings are not equally susceptible to the diphtheritic 
poison. Animals which are refractory to the living bacillus are equally 
so to the toxine. 

Of the animals easily poisoned we must mention the guinea pig. 
The rabbit is quite resistant, the dog much more so, and the mouse 
and the rat endure high doses. 

Subcutaneous injection produces oedema in the guinea nig^and 
causes death within two or three days. The post-mortem changes 
noted are pulmonary congestion, pleural effusions, and fteniorrhages in 
the suprarenal capsules. In the rabbit the predominant reartuxe^is 
cellular degeneration of the liver and kidneys. 

When deposited upon the surface of even a healthy mucous mem- 
brane the diphtheritic toxine gives rise to the formation of false mem- 
branes. In animals this result has been obtained in the larynx, the 
conjunctiva, and mucous membrane of the vulva. 

Injections of very small doses may give rise to paralysis with 
changes in the nervous system and myocarditis. 

Tetanus. — In the early studies of tetanus complex methods were 
employed. These were subsequently replaced by simpler procedures. 
Brieger isolated a whole series of bases : tetanine, tetanotoxine, spasmo- 
toxine — all three convulsivants, and one base stimulating the salivary 
and lachrymal secretions. 

These bodies act only in enormous doses. In fact, the true poison 
is an albuminoid substance discovered by Knud Faber, and studied 
by Brieger and Fraenkel, Tizzoni and Cattani, and especially by Vail- 
lard and Vincent. 

The poison obtained by nitration of the cultures is of such activity 
that to~^oo~o °^ a cllD i c centimetre suffices to kill a mouse. Injected 
beneath the skin, it causes tetanus after a variable period of incubation. 
According to Courmont and Doyen, the poison acts indirectly; it 
causes the organism to produce a tetanizing poison. This very in- 
genious hypothesis has been the subject of lively discussions and can 
not as yet be considered as absolutely established. Two theories have 
been advanced to explain the mechanism of convulsive phenomena: 
Autokratov, Courmont, and Doyen admit an action of the poison upon 
the sensory nerves; Brunner admits a modification of the spinal cord 
similar to that produced by strychnine. 

Cholera. — The choleraic poison has been successively studied by 
Petri, who considered it a toxopeptone; by Hueppe and Scholl; by 
Gamaleia, who regards it as a nucleo-albumin contained in the bodies 
of the bacteria ; by Sanarelli, Brieger and Fraenkel, Pfeiffer, and espe- 
cially by Eansom. Ransom's researches, completed by those of Metch- 
nikoff, Roux, and Salimbeni, demonstrate that the cholera poison, un- 



166 INTRODUCTION TO THE STUDY OF MEDICINE 

like the preceding ones, resists boiling. Injected into animals, it pro- 
duces prostration, meteorism, and diarrhoea; death supervenes with 
hyperpyrexia. At the autopsy, hyperemia of the intestines, peritoneal 
effusion, and congestion of the liver, kidneys, and, in the guinea pig, of 
the suprarenal capsules are found. 

Gaseous or Emphysematous Gangrene. — The toxine of emphysema- 
tous gangrene, prepared by Besson, produces oedema, which is often 
followed by a slough. 

In symptomatic anthrax there is found a toxine which was pointed 
out by Duenschmann. 

We now come to the group of microbes which have a tendency to 
invade the entire organism. Their chief representative is the Bacillus 
anthracis. 

Anthrax. — Considered as a ptomaine (Hoffa), a toxalbumin 
(Brieger and Fraenkel), an albumose (Sidney Martin), the anthrax 
toxine has been well studied by Marmier. It is primarily found in the 
bodies of the bacteria, and remains inclosed therein if the culture is 
made under favourable conditions; if not, it abandons them and is 
diffused in the surrounding medium. Injected into animals, it produces 
fever and diarrhoea, and causes death by hyperpyrexia and final con- 
vulsions. 

This poison resists heat quite well ; it is attenuated by hypochlorites 
and the iodo-iodide reagent. 

Septicaemia. — It is to the group of bacilli producing hemorrhagic 
septicaemia that the microbe of chicken cholera belongs. We have 
already referred to Pasteur's experiment upon the narcotic poison con- 
tained in bouillon cultures. It may be well to mention some researches 
demonstrating that the various microbes of this group likewise pro- 
duce toxic albuminoids (Schweinitz, Voges). 

Similar demonstrations have been made regarding the Bacillus pro- 
teus vulgaris, Bacillus pyocyaneus, and Bacillus septicus putidus. 

Colibacillosis. — The important part played by the colon bacillus 
group, even in normal states of the organism, renders necessary a spe- 
cial mention of it in the rapid review here presented. 

The soluble products of the microbes belonging to this group have 
been studied by Denys and Brion, and especially by Gilbert. Their 
action is the more marked the stronger the virulence of the germ em- 
ployed and the older the culture. Nevertheless, to bring about a fatal 
termination, quite high doses are generally necessary, varying from 37 
to 74 cubic centimetres per kilogramme. In the animals under ex- 
periment the result is very marked nervous phenomena, notably tetani- 
form convulsions. 

With a sample derived from dysenteric stools, we obtained an 



GENERAL PATHOGENESIS OF THE INFECTIOUS DISEASES 167 

extremely active toxine : a dose of half a cubic centimetre injected into 
the veins of a rabbit of 2 kilogrammes weight caused death with an 
intense diarrhoea and fever. Greater doses, as high as 15 to 20 cubic 
centimetres, administered to animals caused death with hypothermia. 

Under normal conditions the colon bacillus constantly secretes in 
the alimentary canal poisons which are partly destroyed by the intes- 
tinal epithelium, partly arrested by the liver, and the excess contributes 
to the toxicity of the urine. 

This is observed in quite a number of general diseases, even when 
the intestines are not involved, in which the colon bacillus becomes 
more active and produces a greater amount of toxic substances by 
virtue of organic disturbances. 

Typhoid Fever. — The typhoid toxine has been studied by a great 
number of investigators, among whom it is convenient to cite espe- 
cially Chantemesse and Widal, Sanarelli, Brieger, and Fraenkel. 

Chantemesse utilizes a special medium: it is a cold maceration of 
spleen and bone marrow to which is added a small amount of human 
blood. The maximum of toxicity is observed from the fifth to the 
sixth day. Inoculated into animals, this toxine produces different 
effects according to the dosage : A large dose causes diarrhoea and 
produces death with hypothermia. With a weaker dose, the first phe- 
nomenon is a paroxysm of fever, and the animal succumbs by cachexia. 

At the autopsy, abundant yellowish diarrhceal fluid is found in the 
intestines; the spleen is highly coloured. The urine is seldom albu- 
minous. 

Streptococcus. — Cultures of streptococcus, especially when pro- 
tected from air, contain substances which exert a marked action upon 
the nervous system, bringing in its train rapid emaciation, paralyses, 
and death within two or three days. The active substance is precipi- 
tated by alcohol; it is partly destroyed by heat. 

Staphylococcus. — Staphylococcus generates multiple toxic products, 
of which Eodet and Courmont have made an excellent study. 

Its cultures contain a pyogenic substance precipitable by alcohol, 
and substances soluble in this liquid, which predispose to infection, 
and others which provoke a vaso-dilatation. The substances precipita- 
ble by alcohol provoke trembling, tetaniform convulsions, and produce 
death within a few hours. The substances soluble in alcohol produce 
anaesthesia and kill by arrest of the heart's action. 

Glanders. — The soluble products of the bacillus of glanders, stud- 
ied first by Finger, produce rapid death, or, if the dose be less strong, 
provoke paralyses and death by cachexia. 

One of the most important properties of the sterilized cultures is 

that their injection causes a very notable rise of temperature in ani- 
12 



168 INTRODUCTION TO THE STUDY OF MEDICINE 

mals affected with glanders. This result, discovered by Kalning, has 
been turned to use in practice. A lymph is prepared and frequently 
employed in veterinary medicine for the diagnosis of latent or sus- 
pected lesions. 

Tuberculosis. — The action of glanders lymph may be compared to 
the action exercised by Koch's lymph or tuberculin. The injection of 
the latter is also followed by a reaction in tubercular subjects. But 
tuberculin, prepared by concentrating the cultures or by triturating the 
bacilli, does not represent the true soluble products — that is, the pri- 
mary substances. Of the latter there are many. There are a hypo- 
thermizing toxalbumin; a ptomaine, which causes dyspnoea, hyper- 
pyrexia, and produces death within two or three days; a toxalbumin, 
producing foci of necrosis at the site of injection ; and a toxalbumose, 
which lowers the temperature of healthy animals and gives rise to con- 
gestive and febrile reactions in tubercular subjects. There also have 
been found in cultures or extracts prepared from the organs of tuber- 
cular animals substances the injection of which has been followed by a 
progressive emaciation. Besides the matters contained in the cultures, 
we must mention those encountered in the protoplasm of the bacilli; 
Koch has discovered therein a pyogenic substance. Prudden and 
Hodenpyl have shown that the dead bacilli possess the property of 
causing the formation of granulations similar to tubercles. 

TOXINES PRODUCED BY NONBACTERIAL INFECTIOUS AGENTS 

The investigation of toxines produced by infectious agents higher 
than bacteria has seldom been undertaken. This is due to the fact 
that most authors, persuaded that the bacteria have a monopoly of 
producing infections, have not attached sufficient importance to the 
problem. Those who have attempted experiments have generally 
arrived at negative conclusions. 

It is to be remarked, first, that every parasite causing the develop- 
ment of a lesion secretes or contains a toxic substance; otherwise, it 
would have been perfectly endured by the tissues. This remark is 
applicable even to inanimate substances; they do not act unless they 
are soluble. On the other hand, the fact that toxines are absent from 
a culture bouillon does not warrant the conclusion that they are not 
produced in the living organism. In the case of a great number of 
pathogenic bacteria, in order to prove the presence of a toxine, it is 
necessary to utilize the most complex media and vary the procedures 
of sterilization. In ordinary bouillon, most bacilli produce no appre- 
ciable quantity of poisons. 

When we see a parasite induce grave or fatal disorders, even when 
it remains localized at some point of the organism, we are forced to 



GENERAL PATHOGENESIS OF THE INFECTIOUS DISEASES 169 

admit that it has engendered some soluble product. In this respect 
nothing is more instructive than the history of Oidium albicans. This 
vegetable, inoculated beneath the skin or in the peritoneum, can pro- 
duce nervous troubles — paralysis or movements of rotation around the 
longitudinal axis. The animals succumb within from three to fifteen 
days ; the autopsy proves the absence of all visceral lesions, and that 
the parasite has not left the point where it was introduced. It is 
therefore impossible to explain the phenomena and death except by 
the absorption of some toxic matter. 

In order to render the hypothesis incontrovertible, the poison must 
be discovered in the cultures. In injecting into rabbits cultures steril- 
ized by heat, it is found that the more virulent the specimen employed 
the greater is the toxicity. With a less active parasite, 10 or 12 cubic 
centimetres will provoke no trouble whatever; with an intensified vege- 
table, 5 cubic centimetres will cause death. The dose is doubtless very 
high, if it be compared with the one which kills in cases of diphtheria 
or tetanus; but it is not greater than that which must be employed 
when the typhoid bacillus is used. Moreover, the parallelism existing 
between the increase in virulence and the toxicity is a good demonstra- 
tion of the role played by the oidium poison in the production of the 
phenomena caused by the living cultures. 

On the whole, it seems to us permissible to attribute a general 
bearing to the facts that have been observed, and to conclude that 
all infectious agents act by toxic substances. The latter are not, in 
most cases, sufficiently known from the chemical point of view. The 
results of experimentation have demonstrated their existence and plu- 
rality. The fact heretofore referred to, that the toxicity of the blood 
and the urine is augmented in the course of infectious diseases, is a 
further proof of the formation and importance of microbic poisons. 

Action of Toxines. Eeaction of the Organism 

The toxines, the origin of which we have briefly indicated, produce, 
as we have said, a local lesion, and, at the same time, may impregnate 
the entire economy. 

Locally, they alter the cells with which they come in contact. If 
they be very energetic, they destroy them; if they be less active, they 
induce degenerations followed by reactionary phenomena. The por- 
tion of soluble substances that passes into the circulation will effect 
similar modifications in the rest of the organism. According to the 
activity of toxines, the cells of the organs and of the tissues will perish 
or present more or less profound degenerations. 

We have thus far supposed that the organism was absolutely pas- 
sive — that it did not interfere with the devolpment of the microbe any 



170 INTRODUCTION TO THE STUDY OF MEDICINE 

more than an inert liquid would; in reality, the phenomena are much 
more complex. 

When a microbe penetrates some point of the organism, it finds 
itself plunged into fluids endowed with a certan antiseptic power. 
This is what is designated as germicidal action. If the microbe is but 
slightly resistant, it will be completely destroyed ; if it is more vigorous, 
it will be only weakened, and after a first defeat will gain the upper 
hand and begin to multiply. Then a new mode of defence sets in. 
The leucocytes contained in the blood do an incessant patrolling; they 
guard the integuments and mucous membranes, run to wherever there 
is the slightest abrasion, and even pass through the mucous membranes 
to penetrate into the cavities, there to exercise their role of protectors. 
Every microbe tending to invade an organism will then find itself in 
the presence of migrating cells, always ready to- re-enforce the fixed 
cells and exercise a phagocytic role. 

If the microbe is very virulent, its multiplication is scarcely hin- 
dered; it develops and secretes noxious substances. The cells nearest 
the microbic focus may perish ; the others will present reactionary phe- 
nomena often ending in a proliferation, with a return to the embryonic 
state and in a reappearance of their phagocytic power. The local reac- 
tions thus result in the increase of one of the defensive measures of 
the organism. 

At the same time the toxines which invade the organism by absorp- 
tion modify the nutrition of the cells, and the latter begin to elaborate 
their products on a new plan. It is known that the humours of the 
organism represent the product of the cellular secretions ; there is thus 
a production of substances useful to the organism, some as germicides, 
others as antitoxines. 

The germicidal substances which exist in small amounts under 
normal conditions render the medium unfavourable to the microbe; 
they exercise on it five species of actions: (a) They destroy it; (b) 
hinder its evolution; (c) or at least modify its form; (d) disturb its 
functions; and (e) cause its attenuation. 

The antitoxic substances are those which no longer act on the 
microbe, to lessen its pathogenic potency, but upon the animal 
organism, to strengthen its resistance. They impregnate the cells, 
and thus shield them against the influence of toxines. They act, 
then, in a complex manner, by a roundabout mechanism, and not, 
as was once supposed, by neutralizing the toxines as an acid neu- 
tralizes a base. 

If these favourable secretions be not called into play too late, and 
if they be produced with energy, the course of the disease will be hin- 
dered or arrested. If, however, their appearance be tardy and their 



GENERAL PATHOGENESIS OF THE INFECTIOUS DISEASES 171 

quantity insufficient, the organism will succumb in spite of the devel- 
opment of a certain degree of bactericidal power. 

The humoral modifications, the mechanism of which has just been 
indicated, bring about a weakening of the microbes and favour the 
protective action of the cells. 

We have already stated that at the point where the microbe is in- 
troduced cellular proliferations occur; at the same time certain cells 
succumb; they then assume the nature of foreign bodies, excite the 
nervous system, and induce a vaso-dilatation at the invaded site 
through reflex action. The leucocytes, according to the process discov- 
ered by Cohnheim, leave the blood vessels and migrate to- the affected 
region ; they are attracted by the microbic products and cellular waste, 
which possess the property 'of so-called positive chemiotaxis. Then a 
struggle ensues between the cells and the microbes, the successive 
phases of which have been unveiled by Metchnikoff in a series of ad- 
mirable investigations. The cells take up the microbes, incorporate 
them, and cause them to disappear by a process of intracellular diges- 
tion. This is what is designated as phagocytosis. Unfortunately, the 
phagocyte is not always the stronger; overcharged with microbes, it 
may perish, sometimes after having again entered into the circulation; 
the auxiliary of a while ago will then transport germs and serve to dis- 
seminate infection. 

The fixed cells of the tissues may come to the assistance of the 
leucocytes; the round cells of the connective tissues, Eanvier's clas- 
matocytes, having returned to their embryonic form, and certain cells 
of the hepatic or renal parenchyma, and the vascular endothelium, 
exercise a similar phagocytic role. 

It remains to view the cases in which the microbe invading the 
organism is endowed with extreme virulence. Here no struggle is 
possible. The microbe finds in the humours an excellent medium for 
its development; it increases, produces negative chemiotactic sub- 
stances — that is, substances capable of repelling the leucocytes — and 
gives rise to toxines which overwhelm the economy. No defensive reac- 
tion whatever can occur. 

It is quite certain that between these different modes of infection 
innumerable transitions exist. It is possible, nevertheless, to sum up 
the various events as follows : 

1. Nonvirulent microbe : Destruction by fluids normally germicidal. 
No disturbance. 

2. Slightly virulent microbe : Destruction commenced by the germi- 
cidal humours and completed by the phagocytes; local lesion without 
gravity. 

3. Virulent microbe: Formation of local lesion not constant; im- 



172 INTRODUCTION TO THE STUDY OF MEDICINE 

pregnation of the cells of the organism; cellular reaction resulting in 
the production of germicidal substances — i. e., increasing the resistance 
of the cells. The germs, overcome by the humours, are destroyed by 
the phagocytes attracted by the positive chemiotactic properties of 
microbic products and cellular waste. 

4. Very virulent microbe: Defeat of the organism. Very little or 
no cellular reaction; little, if any, humoral modification. Phagocytes 
repelled by the microbic secretions, which are endowed with negative 
chemiotactic power. 

We shall consider all these phenomena, especially when treating 
of inflammation, immunity, and vaccinations. 



CHAPTER X 
NERVOUS REACTIONS 

Role of nervous reactions in physiology and in pathology — Local and general reac- 
tions : causes of their variations — The different varieties of nervous reactions : 
psychical, sensory, motor, vasomotor, nutritive reactions — Nervous fever — 
Nervous shock. 

All vital acts are but reactions aroused by external agents. Cer- 
tain reactions are produced at the very point where the stimulus acts ; 
these Dr. Bouchard calls autonomous elementary reactions. Others, 
more complex, are caused by modifications in the nervous system ; these 
are the reflex actions properly so called. Their points of departure are 
all the terminations of centripetal nerves — i. e., nerves of general, spe- 
cial, or visceral sensibility. They result in psychic, sensory, motor, 
vasomotor, secretory, and trophic modifications, which are produced 
either at the point of departure by a sort of reflection comparable to 
that of a shuttle, or ending in more or less distant and multiple points. 

The stimulations which serve as starting points for nervous reac- 
tions are continual, though often unconscious; they are indispensable 
for the regular performance of vital actions; they maintain the nerv- 
ous centres in activity. Even under normal conditions they present 
incessant variations. The modifications of the barometer and ther- 
mometer influence considerably our psychical and physical aptitudes. 
It is a fact of common observation that one has not the same ideas, 
feelings, and energy at different seasons, even at different hours of the 
day. Rainy weather or excessive heat diminishes muscular energy; 
fresh air, and notably sea air, increases our activity. On the other 
hand, psychic influences can modify considerably the state of our organ- 
ism, and, conversely, the derangements of our organs reflect on our 
ideas. The slightest gastrointestinal disorder engenders sadness and 
melancholy. All these variations are yet of a normal order; they do 
not constitute sickness, but often predispose to it. 

Local and General Reactions. — The results of nervous reactions 
should be studied, as already stated, both at the point of their depar- 
ture and at a distance from it. 

173 



174 INTRODUCTION TO THE STUDY OF MEDICINE 

Locally, a stimulation is expressed, in certain cases, by an abrupt 
and unconscious movement. When a hot object is touched unwittingly, 
the finger is withdrawn often even before the painful sensation has 
been felt. In other instances, a vasomotor modification takes place. 
Under the influence of a cold application the vessels contract and the 
part becomes bloodless. In case of a hot application, the reverse takes 
place. Finally, if an irritating agent enters the tissues, the result is an 
active congestion followed by oedema and diapedesis. 

Along with the local manifestations, which are all of a defensive 
character, modifications occur at distant points, sometimes at sym- 
metrical points. Taking up an experiment of W. Edwards, Brown- 
Sequard and Tholozan demonstrated that if one hand is dipped in 
cold water the temperature of the other hand goes down. The effect 
is not due to a loss of heat, but to an homologous and symmetrical 
reflex action. In certain cases the phenomena are dissimilar; an 
equilibrium is produced between the peripheral and central circulation. 
In still other cases the manifestations are more complex; the section 
of a nerve may produce zones of anaesthesia or hyperaesthesia at points 
having no connection with the distribution of the sectioned nerve. 

There remains a third group, which comprises the general reactions 
following a local disorder: these are chills, delirium, convulsions, syn- 
cope, fever, and nervous shock. 

Conditions causing Variations in Nervous Reactions. — The phe- 
nomena of reaction vary in intensity according to their point of de- 
parture. They are the more marked as the region stimulated is the 
more richly supplied with nerves. If, for example, the snout of a 
rabbit is briskly dipped in cold water, a respiratory syncope results; 
if its hind legs are plunged in — that is, a region more extensive but 
less rich in nerve endings — no notable trouble is observed. 

It is readily understood that the intensity of reactions increases as 
does the excitability of centripetal terminations ; frictions, the applica- 
tion of sinapism, the action of heat, by flushing the skin, render the 
sensibility keener and the reactions more energetic; conversely, cool- 
ing and local anaesthetics, such as cocaine, diminish or suppress the 
effects of reaction. It must only be added that, under these various 
conditions, the phenomena are more complex than might be supposed. 
When the nerve terminations are modified, there are modified thereby 
the stimulations which maintain the tension of the nervous centres 
and their reactionary aptitude. 

We may, in reality, act upon the centres by acting on the periphery. 
We may also directly act upon them, for instance, by means of sections 
which, by abolishing certain restraining influences, increase the re- 
sponsive power of other parts. Likewise, under the direct influence of 



NERVOUS REACTIONS 175 

heat or cold, the nervous centres become more or less apt to act. It is, 
however, the toxic substances that generally intervene: the bromides, 
opium, and chloral hydrate exercise a well-known sedative influence, 
while strychnine causes spinal excitability to so high a pitch that the 
slightest stimulation provokes violent tonic convulsions. 

Alterations of the pathways of transmission are by no means less 
important. If they affect the centripetal paths the result is retarda- 
tion or trouble in the perceptions and reactions. If the centrifugal 
paths are the seat of alterations, at times cramps or contractures, and 
at other times trembling and -irregular or insufficient movements, are 
observed. 

In other instances the organs in which the reflex action ends are 
altered and present very grave disorders under the influence of the 
slightest peripheral stimulation. The most striking example is offered 
by cardiac pathology : a slight impression, which provokes simply some 
palpitation in a healthy man, may in a person affected by myocarditis 
or aortic insufficiency give rise to a fatal syncope. 

Even in the normal state, nervous responses vary with a great 
number of predisposing conditions, which we must now rapidly pass 
in review. 

It is, in the first place, the influence of the species. The higher 
the being, the more energetic are the reactions. Stimulations that 
elicit no response in animals may cause accidents in man: a violent 
blow on the testicles is well endured by a dog; in man it not infre- 
quently causes a lipothymia or a syncope. The nervous shock is like- 
wise rare in animals, or occurs only under the influence of exceedingly 
violent causes. 

To confine ourselves to the human species, we shall first note the 
influence of sex. In women, nervous reactions are far more easily 
called forth than in men ; women blush or grow pale, laugh or cry, on 
the slightest pretext. In order, however, to fully appreciate the differ- 
ences, we must consider the genital period. In young children the 
nervous system is always of a feminine character; it is a matter of 
common observation that with them reactions are quick, mobile, and 
excessive. At an advanced age sexual differences become less marked: 
from a physiological as well as a psychical standpoint the old man 
is a being who reacts little ; the strongest impressions leave him almost 
indifferent. Likewise, when an infectious disease breaks out, the reac- 
tions, so tumultuous in the child, so marked in the adult, are hardly 
noticeable in the aged, and we are greatly surprised, at the autopsy, 
to find, for instance, a pneumonia arrived at the stage of gray hepati- 
zation without its existence having been revealed by any symptom 
whatever. 



176 INTRODUCTION TO THE STUDY OF MEDICINE 

Age and sex differences aside, there are numerous factors which 
intervene to impress the nervous system with special reactionary apti- 
tudes, and thus confer on the individual a personality. The most 
important are the hereditary and inborn influences. 

Psychical characteristics and reactionary tendencies are transmitted 
from parents to children. Of this we shall treat at length in the fol- 
lowing chapters. All the children of the same family are not abso- 
lutely alike ; their responsive aptitudes are often very different, because 
the state of the nervous system in the parents has not been the same 
at the different periods of life. The nervous system of a child repro- 
duces the nervous systems of the parents, such as they were at the 
epoch at which conception took place. 

In general, children born of young parents are more apt to react; 
they are more lively and more cheerful. But when the generators are 
older, and have experienced disappointments and disillusions which are 
almost unavoidable, and their nervous systems have undergone the 
shocks of external events and they have acquired that sort of sadness 
which characterizes mature age, then the child comes to the world 
calmer; it will not have the illusions and enthusiasms of those born 
before it ; it will often be inclined to melancholy. If conception is still 
more tardy, the child will be recognised by its lack of youthfulness, its 
precocious senility, which seems to continue the senility of its parents. 

In the next place, the state of mind, the physical and psychical con- 
ditions that existed at the moment of conception or during gestation 
must be noted. In these cases the influence of the father is naturally 
less marked, as it acts only during the period of formation of the 
spermatozoids ; while the mother's influence makes itself felt alike 
during the development of the ovum and the entire duration of preg- 
nancy. It even seems that the disturbances of infectious or neuro- 
pathic origin occurring during gestation have a far greater influ- 
ence on the product than those existing at the moment of conception. 

The incessant modifications transmitted by heredity explain the de- 
velopment of races and the influence of civilization. The effect of the 
latter is to diminish the intensity and fatality of nervous reactions. 
It can be said of the savage what Virchow said of the child: he is 
a medullary being. In the civilized adult the brain is predominant 
and rules the subjacent centres ; thus is created the will which becomes 
capable of arresting various reactions, even the vasomotor reactions; 
it becomes possible to refrain from crying under the influence of pain, 
and from flushing or getting pale under the influence of emotion. It 
happens, however, that at a certain moment the will, even the most 
energetic, undergoes more or less lengthened eclipses. In the course 
of diseases or during convalescence the highest psychical manifesta- 



NERVOUS REACTIONS 177 

tions are weakened, and, consequently, nervous reactions assume that 
character of fatality which they seemed to have lost in the superior 
races. 

Nature of Nervous Reactions 

Psychical Reactions. — In their highest manifestations nervous re- 
actions are expressed by phenomena of an intellectual order. We have 
already established that all ideas have an external origin. According 
to the old adage, so passionately criticised by the spiritualist school, 
it can still be maintained that all our present acquisitions have origi- 
nated from sensitive and sensorial impressions. But while rejecting 
the existence of innate ideas, we must recognise that the human brain 
presents from birth certain special aptitudes. We inherit, to a certain 
extent, the experience acquired by our parents. It is quite certain 
that the brain of a child born of civilized parents must not have the 
same intellectual predispositions as the brain of one born of savage 
parents, and it is hardly probable that the son of the primitive man, 
if he were possibly transported into our world, would be able to acquire 
the knowledge inculcated in the children of our epoch. 

The intellectual and moral properties thus developed in races and 
families may become perverted in a great number of diseases. At the 
present day we no longer question the influence of the body on the 
mind. It is a commonplace truth that character, intelligence, and 
capacity for work are considerably modified in the course of most 
diverse diseases. The sadness and hypochondriasis of individuals suf- 
fering from gastric, intestinal, hepatic, or genito-urinary affections and 
the delirium incident to febrile diseases are facts so open to common 
observation that we do not need to dwell on them. Eeciprocally, psy- 
chical impressions modify our bodily state. Emotion provokes polyuria 
or diarrhoea and arrests digestion. It even suffices that the mind should 
fix itself on an idea in order that there be produced a series of almost 
imperceptible movements which are but a tendency to the act. Hence 
by perception of such abortive movements the possibility for those 
endowed with a very keen tactile sensibility to read thoughts. 

Sensory Reactions. — Reactionary manifestations often affect the 
sensibility. A nervous excitation may produce anaesthetic or hyper- 
aesthetic phenomena : a superficial pain cures a profound pain. Brown- 
Sequard has shown that the projection of a current of carbonic acid 
on the larynx is followed by a cutaneous anaesthesia. In a subject 
with a predisposed nervous system, for instance an hysterical woman, 
even a slight traumatism may give rise to a sensitivo-sensorial hemi- 
anaesthesia — viz., to abolition of general and special sensibilities on 
one side of the body. 



178 INTRODUCTION TO THE STUDY OF MEDICINE 

Motor Reactions. — Eeactions occurring in the motor sphere are 
far more numerous. The best example is afforded by the tickling of 
the sole of the foot. At first, the leg is abruptly withdrawn, even in 
sleep; this is the plantar reflex. If the stimulation be kept up, the 
individual raises both feet : then a nervous rictus, spasms, and, finally, 
convulsions follow. If a more sensitive person is operated upon, con- 
vulsions appear far more readily. With children the slightest irrita- 
tion is enough — a fish bone fixed in the tonsil, an intestinal worm, and 
the pain of teething are familiar causes. 

Considering the same influences in an hysterical person, it must be 
noted that the most trifling excitement may call forth grave mani- 
festations. A slight shock may give rise to paralysis, trembling, or 
contracture. These various symptoms do not appear at once; response 
is slow; the individual must muse on his accident, and induce, so to 
say, self-suggestion in order that morbid manifestations be aroused. 

In certain cases the frequent repetition of the same act is followed 
by contractures called functional cramps; such are the cramps of 
writers, telegraphers, and pianists that are observed in individuals pre* 
disposed by some nervous taint. 

Excitations also give rise to inhibitory phenomena, which are to 
be well distinguished from paralytic manifestations. Inhibition is an 
active phenomenon. For instance, the stimulation of the pneumogas- 
tric nerve causes arrest of the heart through inhibition. In medicine 
we often see a violent stimulation to determine an arrest of circula- 
tor}'' or respiratory movements, or, as is commonly said, a circulatory 
or respiratory syncope. In the same order of ideas we may mention 
the impossibility of motion experienced by individuals when under the 
influence of a violent emotion. At a higher degree — that is, in a pre- 
disposed subject — an attack of catalepsy occurs. 

Vasomotor Reactions. — Another group of nervous responses is con- 
stituted by vasomotor reactions. Every stimulation, especially if pain- 
ful, determines a vaso-constriction, even when the subject is anaesthe- 
tized. Vasomotor modifications are observed every moment in physiol- 
ogy as in pathology. We need barely mention the well-known influ- 
ence of heat and cold. In the case of a chemical agent a congestion 
is produced, followed by an exudation, which dilutes or neutralizes the 
noxious substance. But it is in the struggle against infectious agents 
that the role of vasomotor responses intervenes most efficiently; the 
active congestion permits diapedesis, and thereby phagocytosis. 

When a vasomotor modification takes place at one point of the 
economy, others are generally produced in more or less distant parts. 
An equilibration is often admitted between the superficial and the 
profound circulations, and it is upon this idea that revulsive medica- 



NERVOUS REACTIONS 179 

tion is based: dry cupping, by drawing the blood toward the skin, is 
supposed to relieve the congestion of the subjacent parts. The facts 
are real, but they are more complex than was formerly believed. In 
some instances the variations occur in the same direction; thus, the 
application of the ice bag to the cranium excites the vaso-constriction 
of the meningeal vessels. Fredericq, who has proved the fact experi- 
mentally, remarks that the phenomenon is produced too quickly to be 
attributed to a reduction of heat; it is a manifestation of a nervous 
order. Similar phenomena must occur in many cases, and it is prob- 
able that an attack of cold that gives rise to pneumonia must act 
by first producing a vaso-constriction of the pulmonary blood vessels. 
The congestion revealed by clinical examination represents already a 
phenomenon of reaction. 

Under the influence of a unilateral stimulation, symmetrical vaso- 
motor responses are often produced, whether of the same or of a con- 
trary kind. Thus, if one hand is exposed to cold, the other also grows 
cold. On the contrary, congestion of one of the kidneys induces 
anaemia in the other ; extirpation of the superior cervical gland of the 
sympathetic, which produces vaso-dilatation in the enervated ear, de- 
termines vaso-constriction in the intact ear. 

In a great number of instances circulatory disturbances have their 
starting point in some distant organ. Stimulation of the biliary 
passages, as is realized by lithiasis, produces in the lungs vaso-con- 
striction, followed secondarily by congestion. It is a reflex action fol- 
lowing the sympathetic both as a centripetal and a centrifugal path. 

If the phenomena are very intense, the vessels overfilled with blood 
may burst. A cold bath has been able to produce cerebral hemorrhage, 
anger has been followed by epistaxis. Cerebral lesions are capable of 
producing subpericardiac and subpleural ecchymoses, or even veritable 
foci of pulmonary apoplexy. 

Vasomotor disturbances often terminate in the production of 
oedema. It is demonstrated that venous obstructions are generally 
insufficient to permit serous transudation; there must be, in addition, 
some vasomotor trouble. If the three veins of the base of the ear of 
a rabbit be tied, no disturbance is observed; but if we then extirpate 
the upper cervical gland of the sympathetic, oedema of the pavilion is 
produced. 

The vasomotor disturbance so decidedly represents the principal 
factor that, under certain pathological circumstances, it suffices to give 
rise to oedema. It is thus that a whole series of cutaneous manifesta- 
tions develops, especially urticaria and fluxions, which, in arthritics, 
are observed in the eyelids in consequence of a cold draught. Under 
similar circumstances arise also the pseudo-lipomata of rheumatics. 



180 INTRODUCTION TO THE STUDY OF MEDICINE 

Secretory Reactions. — Whether there be or not any vasomotor 
modification, the nervous system may call into action the glandular 
secretions. We have already referred to emotional polyuria and diar- 
rhoea; we shall add the sweats, and notably the cold perspirations, 
which represent the most remarkable example of dissociation between 
secretory and vasomotor phenomena. In other cases, the sweats, far 
from being increased, diminish or are suppressed: a violent emotion 
produces dryness in the throat ; a blow upon the abdomen or a crisis of 
hepatic colic gives rise to a transitory anuria. It may be stated that, 
as a rule, slight stimulations increase the secretions and that violent 
stimulations diminish them. This can be experimentally demonstrated 
by stimulating more or less the sciatic nerve. Neuralgia of this same 
nerve gives similar clinical results : if of moderate intensity, it increases 
diuresis ; if violent, it gives rise to oliguria. 

Nutritive Reactions. — One of the most interesting functions of the 
nervous system consists in regulating the movements of nutrition. Its 
influence upon the carbohydrates has been easily recognised. An emo- 
tion produces a transitory glycosuria in certain individuals ; but if the 
unhealthful excitations be repeated, glycosuria becomes permanent: a 
nervous diabetes develops. 

Similar modifications occur in nitrogenous substances. There are 
albuminurias caused by nervous reactions; they occur as the result of 
cutaneous stimulations — for instance, when an individual suffering 
with psoriasis scratches himself. They are observed also in consequence 
of strong psychical emotions. At other times the disturbance in the 
elaboration of nitrogenous substances is expressed by modifications in 
the urea. This result has been turned to account by therapeutists : in 
order to increase the production of urea, cutaneous frictions with 
horsehair gloves, douches, or a sojourn on the seashore are prescribed. 
Analysis of the urine demonstrates that sea air increases by 3 grammes 
daily the excretion of urea; sea bathing produces an increase of 1 
gramme, and a bath in hot sea water 2 grammes. In all cases cutane- 
ous stimulation favours oxidation. 

Likewise, it has been demonstrated that pleasant impressions, joy, 
happiness, raise the quantity of urea. Bocker has seen an individual 
lose, under the influence of a great joy, 1,159 grammes of his weight 
and eliminate through his urine 40 grammes of urea in twenty-four 
hours. This loss, which expresses an increase in nutritive ex- 
changes, is followed by an increase of appetite and an energetic repa- 
ration. On the other hand, depressing causes, sad news, diminish 
oxidation and hinder assimilation; the sensation of hunger grows 
less lively and emaciation makes rapid progress. In certain instances 
nervous stimulation, whether physical or ps} T chical, a blow upon the 



NERVOUS REACTIONS 181 

head or an emotion, may engender a permanent disorder of nutri- 
tion — viz., azoturic diabetes. 

Although the fact is not demonstrated, it is probable that the nerv- 
ous system intervenes in the elaboration of uric acid, and, consequently, 
in the pathogenesis of gout, since fatigue, excesses, and anxieties play 
an important part in the causation of the disease. 

The trophic influence of the nervous system accounts for certain 
disturbances which one might at first be tempted to explain by an- 
other mechanism. Thus, articular lesions are followed by atrophy of 
the muscles subjacent to the diseased joint. The phenomenon is not 
due to the immobility of the member, but to a true reflex. By severing 
the posterior roots in a dog, Raymond and Deroche found that the 
traumatism of the knee did not produce amyotrophy: they had sup- 
pressed the centripetal portion of the reflex arch. 

Trophic disturbances may also be responsible for pigmentary phe- 
nomena. Many a dyschromia is due to some nervous influence. The 
most curious instance is that recorded by Gubler: In a man suffering 
from trifacial neuralgia the hair grew without colour during the crisis, 
so that after a certain number of attacks it presented a zebralike 
appearance. 

By controlling nutrition, the nervous system also regulates the 
temperature. There are nervous fevers, of which hysterical fever is 
the most familiar type. 

When an individual is weakened by any cause whatever, and par- 
ticularly by a disease, the slightest excitement produces fever. An- 
noyance raises the temperature of the sick ; when patients hate to take 
cold baths, it is often observed that, after a forced immersion, the 
thermometer rises a few tenths of a degree, despite the loss of bodily 
heat. It is a familiar fact in hospitals that the temperature of the 
patients increases on visiting days. In the convalescents it slightly 
rises when they are permitted to make their own toilet or to read. 

Reciprocally, nervous reactions may cause a diminution of tem- 
perature. This is at least what occurs under the influence of violent 
impressions, which often give rise at the same time to a series of mani- 
festations collectively called nervous shock. 

Nervous Shock. — Nervous shock is essentially characterized, from 
a pathologico-physiological standpoint, by arrest of exchanges between 
the cells and the plasmas (Brown-Sequard) ; in other words, it is an 
arrest, or rather a diminution, of nutritive activity occurring through 
reflex action, under the influence of a sudden and violent excitation. 
It is an active phenomenon, and not the result of nervous exhaustion. 
So it is readily understood that shock should be more frequent in men 
than in women, and in adults than in the young and the aged. It is to 



182 INTRODUCTION TO THE STUDY OF MEDICINE 

be noted, however, that when it is produced in the aged it assumes a 
character of exceptional gravity. 

Nervous overexcitement is favourable to the production of shock; 
during the Commune of Paris shock was far more frequently observed 
among the insurgents than the regular troops. On the other hand, 
nervous exhaustion is unfavourable to its development; hence a first 
shock is not aggravated by a fresh excitement. A grievously wounded 
man listens with indifference to the announcement of a catastrophe; 
it would not be so if shock, as is often said, were due to nervous ex- 
haustion. 

Among the causes of shock, great traumatisms must be put on the 
first line, then violent excitations of the cutaneous nerve terminations. 
Whether an immersion be made in boiling or cold liquids, the effect, 
from this point of view is the same. We shall not advert to this ques- 
tion, already referred to on page 43. We have likewise pointed out 
that sideration by electrical currents (page 58) belongs to the same 
order of phenomena. 

In the case of localized stimulation, the effects vary with the re- 
gions; they are the more marked as the part is the more richly sup- 
plied with nerves and more sensitive. It is not, however, the external 
parts alone than can be the starting point of nervous shock; hepatic 
or renal calculi, the colic of intestinal occlusion, and pulmonary or 
cerebral emboli can produce the same effects : these are veritable inter- 
nal trautnatisms. 

Excitation may also be produced by chemical substances, and espe- 
cially by irritating vapours, acting upon the larynx and lungs. Thus, 
chloroform, the effects of which are, of course, complex, may, by stimu- 
lating the terminations of the laryngeal nerves, give rise to a series 
of inhibitory acts — namety, cardiac syncope, respiratory syncope, and 
arrest of nutritive exchanges. 

The last, but not the least, of causes of nervous shock must not 
be overlooked — viz., moral impressions. It is well known that Sopho- 
cles, Denys the tyrant, and Pitt succumbed to the sudden announce- 
ment of some startling news. A great joy or a great fright may cause 
sudden death, or the series of phenomena that characterizes shock. 

An individual suffering with this syndrom, a man, for instance, 
who is the victim of a grave traumatism (such is most frequently the 
case), is in a state of complete prostration. He is lying down, motion- 
less, absolutely indifferent to all his environment and often altogether 
unconscious; the skin is pale, covered with a cold, clammy sweat, the 
mucous membranes are bloodless, and the eyes half closed. When his 
eyelids are raised the pupils are found to be dilated. Sensation is ex- 
tinct, respiration irregular, pulse slow, irregular, and weak; the veins 



NERVOUS REACTIONS 183 

contain but a small amount of blood, which presents a bright colour. 
Peripheral and central temperature goes down ; the thermometer placed 
in the rectum does not rise above 36° C. Death thus supervenes in 
adynamia and collapse. In grave cases, fatal termination occurs 
within a period varying from thirty minutes to twenty-four hours. 
When the evolution is to be favourable, the symptoms gradually disap- 
pear, but they sometimes leave as sequels various nervous disorders : 
disquietude, agitation, neurasthenia, and paralysis. Such cases are ob- 
served especially in consequence of railroad accidents. 

The explanation of these various phenomena is already pointed out 
by the analysis of the symptoms. The modifications of circulation and 
respiration, and the red colour of the venous blood, which, as the 
analyses made by d'Arsonval have shown, contains very little carbonic 
acid, sufficiently demonstrate the profound disturbance of nutrition. 
Cellular life is suspended and modified. The recent researches of 
Philippen established the fact that during shock a veritable auto- 
intoxication is produced as the result of disorders occurring in cellular 
nutrition. The toxic substances thus generated can not pass from the 
cells into the blood, and, on the other hand, toxic products no longer 
pass from the blood into the cells. The most active poisons can be in- 
troduced into the organism with impunity. It has been experimentally 
demonstrated that animals in a state of shock do not respond either 
to strychnine or veratrine ; and clinical experience establishes that it is 
in slight cases alone that alcohol causes semi-intoxication and opium 
induces sleep. 



13 



CHAPTER XI 
DISTURBANCES OP NUTRITION 

The two characteristic phenomena of nutrition : assimilation and disassimilation — 
Cellular nutrition : the six acts to assure it in the higher beings — Disturbances 
of nutrition — Starvation — Disturbances of digestion and absorption — Varia- 
tions of cellular nutrition in physiological and pathological conditions — 
Diatheses. 

Tnutkition" is the principal property of living matter: it essen- 
tially characterizes life. 

It comprises two orders of phenomena : assimilation and disassimi- 
lation. 

Assimilation is represented by a phenomenon of organic synthesis. 
The cell seizes upon the nutritive materials placed at its disposal, 
and groups them together in such a manner as to form a very complex, 
and therefore very unstable, molecule. In order that these phenomena 
may be produced, a certain amount of force must be absorbed — i. e., 
pass into a state of latency. 

Then comes the second phenomenon, disassimilation. The formed 
molecule disaggregates and is reduced to simpler and, consequently, 
more stable elements ; at the same time a certain quantity of energy is 
liberated. Molecular destruction is thus attended with a disengage- 
ment of force ; the wearing out of the cell results in the manifestation 
of life. Thus goes on the process of a continual construction and de- 
struction, and thereby an incessant renovation. 

The substances of disassimilation have become useless. They are 
even harmful, for the cell does not reject them such as it has absorbed 
them; it abandons them in an altered state, unfit for its nutrition. 
They can, however, be utilized by other beings, who will cause them to 
undergo new transformations, and bring them back to their first state. 
So there is a real circulation of matter, which passes from being to 
being and returns to its point of departure. 

To take a concrete example, let us consider how animals and plants 
live. Of course, cellular life is alike in both cases. As Claude Bernard 
184 



DISTURBANCES OF NUTRITION 185 

has shown, there is not a vegetable physiology and an animal physi- 
ology. The laws of nutrition are the same: the plant cell liberates 
force, as does the animal cell, and, like it, produces then carbonic acid. 
But the plant spends much less energy, and the phenomena predomi- 
nant in it are those of assimilation. It seizes upon carbonic acid and 
unites it to water under the influence of solar rays, thus reconstitut- 
ing a hydrate of carbon, which furnishes the animal with vital force. 
It is, then, the sun that, through the plant, furnishes the necessary 
energy; the solar rays, as Herschell has pointed out, are the true cause 
of all nutritive phenomena and the source of all vital energy. 

When a living being is placed in a confined space, there comes a 
moment when the vital manifestations cease. It is not because the 
aliments are exhausted, for these can be supplied without restoring 
life; the vital arrest is due to an accumulation of useless matter — 
namely, to auto-intoxication. The being has poisoned itself by its 
own products. Let these be artificially eliminated, and life will con- 
tinue; let another being of a different nature, capable of turning to 
use the cellular wastes, be introduced into the same space, life will be 
resumed, and, in this manner, there will be realized what takes place in 
Nature. 

If we consider the life of the unicellular being, we see that nutri- 
tion is characterized by four series of phenomena : A physical phe- 
nomenon, endosmose, by which nutritive substances pass from the 
exterior to the interior of the cell; a chemical phenomenon, assimi- 
lation, characterized by an organic synthesis and the storing up of 
force; another chemical phenomenon, the reverse of the preceding one, 
disassimilation, accompanied by a disengagement of accumulated en- 
ergy; finally, a physical phenomenon, exosmose, by which the matter 
which has become useless or harmful is thrown out of the cell. In 
order that endosmose and exosmose may be produced, the nutritive 
substances must be in a state of solution. We can conclude, therefore, 
that to a unicellular being life is possible only in a liquid medium. 

The same is true of the higher beings, so far at least as cellular 
life is concerned. An artifice permits life out of water; that is, the 
creation of an internal medium — blood, lymph, plasma — whence the 
cells draw the elements of their nutrition. In physiology, as in chem- 
istry, active manifestations can not take place unless the substances are 
dissolved. 

Aerial existence presents a new complication. In order that nutri- 
tive materials may reach the medium, and that the products of dis- 
assimilation may be eliminated, it is indispensable that there should 
exist a certain number of organs. Thus the phenomena of nutri- 
tion become complicated. New functions are added; some for the 



186 INTRODUCTION TO THE STUDY OF MEDICINE 

entrance of alimentary substances, others for the rejection of waste 
products. 

We are thus led to admit six successive acts in the nutrition of 
higher beings : 

1. Transmission of food by the digestive canal; transformation of 
aliments by the juices flowing into the gastrointestinal tract. The 
effect of these transformations is to hydrate the substances in order to 
render them dialyzable; the starch is saccharified, the albumins are 
peptonized, the fats are partly emulsified and partly decomposed into 
fatty acids and glycerine. 

2. Absorption. The dialyzable substance passes through the intes- 
tinal walls. But the phenomena are not merely of a physical order; 
there is, at least in some measure, a vital process, in which the epi- 
thelial cells of the intestine take an active part. 

3. Dehydration of the aliments that have been hydrated in the 
gastrointestinal cavity. Had the aliments preserved the power of diffu- 
sion acquired in the intestine, they would be eliminated as fast as they 
were introduced; they undergo, therefore, a process of dehydration, 
which, rendering them less readily dialyzable, adapts them either for 
nourishment or to be stored up in certain parts where they form 
reserves. Dehydration begins in the intestinal walls, where peptones 
form new albumins and the decomposed fats are combined anew; it is 
finished in the lymphatic glands, and especially in the liver, which 
arrests the fatty acids, the peptones, and the sugar. Glucose is dehy- 
drated and forms a matter analogous to starch — namely, glycogen — 
which accumulates in great quantities in various tissues, in the mus- 
cles, and chiefly in the liver. 

4. Nutrition of cells, comprising the four acts above indicated in 
reference to unicellular beings. Only, it is not in the ambient medium 
but in the interstitial plasma that the cells appropriate the matter 
they want, and eject the waste substances. The latter pass into the 
blood and are eliminated. But, in order to easily leave the organism, 
they must become dialyzable. 

5. Transformation of the products of disassimilation, which be- 
come dialyzable. The liver plays here a very important part ; it is in its 
parenchyma that nitrogenous products undergo the ultimate trans- 
formation which reduces them to the state of urea, a crystallizable 
body, which readily leaves the organism, and even acts as a diuretic ; it 
favours the renal emunction. 

6. Eejection of the useless substances by the emunctories, chiefly 
by the lungs and kidneys, and next by the skin and the various glands 
with secretory ducts. 

It is possible, then, to find out, at least approximately, the nutritive 



DISTURBANCES OF NUTRITION 187 

state of a man by examining his excreta. It has thus been established 
that an adult voids in twenty-four hours 250 grammes of carbon and 
18 grammes of nitrogen; he must ingest, therefore, each day, aliments 
that will furnish the same quantities of these two substances. He will 
obtain the 18 grammes of nitrogen by consuming 500 grammes of 
meat, but for the 250 grammes of carbon he will need 2 kilogrammes 
of meat. These figures show the necessity of a mixed alimentation. 
If vegetables are added to the diet, the ration of maintenance is ob- 
tained by giving 5 parts of carbohydrates for 1 part of nitrogenous 
matters. When these conditions are not fulfilled, disturbances break 
out. To understand the mechanism, we must first consider what hap- 
pens in case of absolute inanition. 

Starvation. — When a being is deprived of nourishment, of the two 
acts characterizing cellular nutrition, only one is preserved; disas- 
similation continues, and death supervenes when the body has lost 
about 40 per cent of its weight. All the tissues do not equally take 
part in the emaciation. Fat diminishes in the proportion of 97 per 
cent. The viscera are affected in the following order : First, the spleen, 
and then the liver, the muscles, the kidneys; the most resistant of all 
are the heart and the nerve centres. Their loss does not exceed 3 per 
cent of the initial weight. These various results are easily explained. 
At the beginning of starvation, the sufferer consumes the fat; when 
this is exhausted, he resorts to the nitrogenous substances. At this 
moment, urea increases in the urine, albuminuria sets in, the organic 
temperature falls, and then the situation becomes grave. 

Survival varies considerably, according as one takes or suppresses 
liquids. A dog deprived of nourishment and of beverages succumbs 
in twenty days; a dog deprived of food, but having water at its dis- 
posal, is still living at the end of thirty days, and, if fasting ceases, it 
may recover health. The same differences are observed in the case of 
man, and the celebrated fasters of recent years have always been care- 
ful to continue drinking. Water is beneficial because it washes the 
organism and carries off the products of disassimilation ; it prevents 
auto-intoxication. 

Man is seldom submitted to absolute fasting; there is generally an 
insufficiency of nourishment and a bad quality of food. This is what 
happened during the great famines which ravaged Europe in the Mid- 
dle Ages and until the eighteenth century; that is also what occurs 
during wars in besieged towns. On such occasions a whole series of 
disturbances is observed, mostly due to the secondary action of infec- 
tious germs. Bad nourishment weakens the organic resistance and 
leads to the development of epidemic diseases, markedly of typhus. 

Likewise, in clinics, those who are ill nourished, either in conse- 



188 INTRODUCTION TO THE STUDY OF MEDICINE 

quence of poverty or some organic lesion (a stricture of the esophagus 
or the pylorus), present a series of symptoms, some of which are the 
direct result of starvation, others are due to superadded infections, 
owing to the weakness of the organism. Among the former we shall 
indicate emaciation, anaemia, dropsy, and cardiac and cerebral dis- 
orders, notably delirium; among the latter, cutaneous eschars, pul- 
monary gangrene, blood infections, and especially tuberculosis. 

Nutritive Disturbances due to Disorders of Digestion. — For the 
study of the disturbances of nutrition, we shall review in succession 
the different acts which follow one another in the higher beings. It 
is first, as already stated, the action of the digestive juices which 
hydrate the ingesta. When the aliments are too abundant or of bad 
quality, when they are indigestible or not appropriate to the age, very 
complex disturbances result. The nondigested food falls an easy prey 
to the microbes swarming in the alimentary canal; the result is an 
increase in intestinal fermentation, catarrh, or inflammation of the 
digestive tube, and dilatation of its various parts, markedly of the 
stomach and large intestine. From a functional point of view, an 
attack of indigestion, dyspepsia, sometimes lientery, follows. The sub- 
ject gets thin, nervous manifestations appear, various tissues are dis- 
turbed in the nutrition, and often nodes develop around the second 
phalanges {nodosites de Bouchard). 

At other times, it is the case of those who take in excess some 
particular kind of food ; some, for instance, abuse the carbohydrates : 
a too great amount of glucose is absorbed. The cells are unable to 
utilize all, and some of it passes into the urine ; thus is produced a first 
variety of alimentary glycosuria. In other instances the nitrogenous 
substances are too abundant; they are absorbed, but do not undergo 
their complete circle of evolution; they stop at the stage which pre- 
cedes the formation of urea. According to certain authors, uric acid 
is found in excess, and may pass into the urine or accumulate in vari- 
ous parts of the organism, thus giving rise, at least in some cases, to 
the affection called gout. 

We have already pointed out that the second act of nutrition could 
not be explained by the laws of physics alone, that a large part is due 
to the vital action of the epithelium and membranes of the intestine. 
The peptone, for example, becomes dehydrated while passing through 
the intestinal walls, so that none of it is ever found in the blood, not 
even in the portal vein. Under certain pathological conditions it no 
longer undergoes its transformation into albumin; it passes into the 
system, and, as it is no longer good for nutrition, it is found in the 
urine. In this manner is created the peptonuria of intestinal origin — 
the enterogen peptonuria of the German authorities. 



DISTURBANCES OF NUTRITION 189 

Once absorbed, nutritive substances undergo a final transforma- 
tion in the mesenteric glands and the liver. Physiology has not taught 
us much respecting the function of the lymphatic glands, nor does 
pathology tell us anything about disturbances dependent upon their 
alterations. We are better informed as to the fate of all the substances 
which enter by the portal vein. The liver stops the traces of peptone 
which may have escaped the dehydrating action of the intestine, and it 
modifies the albumins that are not yet quite fitted for the renovation 
of the cells. No wonder, then, that there exist, in liver diseases, ax 
one time peptonuria (hepatogenic peptonuria), at another albu- 
minuria. It is especially on the ternary substances that the liver ex- 
erts its action. It arrests the sugar which the portal vein contains 
in excess after meals; it dehydrates and stores it up under the form 
of glycogen, which it transforms into a new sugar, somewhat different 
from the ordinary glucose, and which it diffuses according to the needs 
of the organism. 

If the liver is altered, the sugar is not arrested; it passes into the 
blood and is eliminated by the urine. This glycosuria also is pro- 
duced after meals ; it is an alimentary glycosuria due to hepatic insuf- 
ficiency. 

Variation of Cellular Nutrition under Physiological Conditions. — 
The variations of cellular nutrition are exceedingly numerous, even in 
the normal state. There exists, nevertheless, a medium type of nutri- 
tion, which is modified, however, according to age. 

During the first years of life, assimilation predominates over dis- 
assimilation; the child accumulates matter; it constructs, so to speak, 
its cells. 

If the alimentation of the infant is bad or insufficient or too' 
copious, gastroenteritis occurs, the stools become green and acid, 
they provoke erythema of the buttocks, vulva, thighs, and even the 
heels. The child loses flesh, and has the aspect of a little old man; 
the skin loses its elasticity, and at the same time the abdomen grows 
large, the liver becomes hypertrophic, the scanty buccal secretion per- 
mits the development of various germs, and aphtha makes its appear- 
ance. Such are the disturbances described by Parrot, in so striking a 
manner, under the name athrepsia. 

In other cases a defective ossification and rachitis are the result. 

In some instances the phenomena are different, either because the 
digestive disorders are not identical, or because the child is born with 
a special inheritance, or because the evil effects of a vicious alimenta- 
tion are aggravated by lack of oxygen and the sun; at all events, the 
child becomes lymphatic or scrofulous. 

At the moment of puberty other disturbances are imminent. At 



190 INTRODUCTION TO THE STUDY OF MEDICINE 

this period a profound modification in general nutrition takes place; 
if the individual is predisposed by a bad inheritance, if his organism 
is weakened by overexertion, if reparation is insufficient, then a gen- 
eral affection — chlorosis — develops. 

Various hypotheses have been put forth concerning the patho- 
genesis of chlorosis. Referred by some to lesions of the vascular sys- 
tem, by others to genital disorders, by others to digestive perturbations, 
and described as a blood disease, chlorosis is most frequently observed 
in children born of tainted parents. Tuberculosis is found in the 
antecedents of three fourths of the patients. It is probable that the 
disorder transmitted by heredity strikes the hematopoietic organs, and 
hinders them from providing for the nutrition required by the addi- 
tional activity. Hence, chlorosis is particularly frequent among the 
young girls of the labouring class who are forced to do too much 
fatiguing work. In the male it is met with, on the contrary, as Dr. 
Hayen has pointed out, among the higher classes, the influence of 
cerebral exertion being, in fact, more detrimental than that of man- 
ual toil, for which man has a greater aptitude. 

We must not, however, deny the part which menstruation may play 
in the genesis of disturbances observed in young girls at puberty. At 
each menstrual period nutritive modifications occur, predisposing to 
disease. The urine contains more urates, the breath and sweat exhale 
a rather strong odour, which is due to an exaggerated production of 
volatile fatty acids. The nervous system, which intervenes so fre- 
quently in the production of nutritive disturbances, may also play a 
part in the development of chlorosis. Not infrequently this particular 
anaemia establishes itself suddenly, or at least in a few days, after a 
strong moral impression — a great fright or a violent sorrow. 

Woman's nutrition is also modified during pregnancy and lacta- 
tion. This is proved by the examination of the urine. With pregnant 
women the cellular wastes are more abundant than normally, and, if 
oxidation be insufficient, organic depuration becomes incomplete. This 
is explained by the frequent appearance of hepatic disorders, the pro- 
duction of albuminuria and peptonuria, and the variations in blood 
and urine toxicity. According to Bunge, important modifications 
occur in the distribution of the iron, previously stored up in the liver, 
where it formed provision for the development of the new being. 

We have already noted that during childhood assimilation pre- 
dominates over disassimilation. In the adult, the two acts of nutri- 
tion balance one another; in old age, disassimilation becomes pre- 
ponderant ; the cells are no longer capable of assimilation ; the cellular 
tissue, the skin, the organs, the skeleton itself, gradually atrophy; the 
integument loses its elasticity, the osseous substance rarefies and be- 



DISTURBANCES OF NUTRITION 191 

comes porous ; hence fractures are easy, and may occur almost without 
cause. This decrease of nutrition predisposes the aged person to chilli- 
ness ; moreover, it reduces his activity and energy and brings on both 
physical and psychical indifference. 

Variations of Nutrition under Pathological Conditions. — Along 
with the modifications occurring under normal conditions, we must 
place those observed in pathology. 

Nutrition may be accelerated, sluggish, or perverted. Setting aside 
the digestive disturbances already spoken of, we shall first consider 
the influence of the nervous system. We have cited many examples 
establishing the fact that general nutrition is profoundly modified 
through the nervous system. For the maintenance of its regularity, 
the continual influence of air and light on our skin is necessary; it is 
therefore disturbed when we live in a confined atmosphere, ( in badly 
ventilated or dark lodgings. It is not any less influenced by all causes 
affecting the nervous system. We have already pointed out the great 
importance, in this respect, of joy and sorrow, of activity and idle- 
ness. Where the influence of the nervous system upon nutrition 
appears most clearly is in the course of neuroses. In paralysis agitans, 
in neurasthenia, the nutritive disorder is expressed by an exaggerated 
excretion of phosphates. This phenomenon is most remarkable in 
hysteria. The amount of urea may fall to 2 grammes in twenty-four 
hours, and even to 75 centigrammes. There is, then, an almost 
absolute arrest of nutrition; hence it is that some hysterical women 
can refuse all nourishment without getting thin in a noticeable degree. 

In some cases modification in the elimination of phosphates is 
observed. It is after an attack of hysteria that a very curious phe- 
nomenon takes place, discovered by Gilles de la Tourette and Cathe- 
lineau. We know that phosphoric acid is eliminated, being united 
to calcium and magnesium (earthy phosphates), to sodium and potas- 
sium (alkaline phosphates). Under normal conditions the proportion 
of the earthy to the alkaline phosphates is as one to three ; after an 
attack of hysteria the earthy phosphates increase and correspond to 
half of the combined phosphoric acid. Such is the phenomenon con- 
stituting a reversion of the formula of phosphates. 

Nutritive modifications may be produced by toxic substances, acting 
on the cells directly, or indirectly through the nervous system. Cer- 
tain medicines, like iodide of potassium, excite disassimilation. 
Others, bromide of potassium, for instance, check it. 

Taken in large and long-continued doses, morphine produces ema- 
ciation ; under the same conditions, alcohol gives rise to obesity. 

Among the substances that produce the most curious effects, lead 
must be mentioned, which disturbs the metamorphosis of nitrogenous 



192 INTRODUCTION TO THE STUDY OF MEDICINE 

constituents, determines an accumulation of uric acid, and sometimes 
gives rise to gout (saturnine gout). 

We know that the microbes act by the poisons they secrete; no 
wonder, then, that infections should provoke numerous nutritive dis- 
turbances. To be convinced of this, it will suffice to remember the 
profound emaciation of the patients. It is, however, the study of the 
excreta that furnishes the demonstrative information. Carbonic acid 
is exhaled in greater quantity, the urine contains an excess of ex- 
tractive matters ; urea decreases, at least in its proportion to the total 
of nitrogen; it is, in fact, replaced by less oxidized substances, by amido 
acids, and even by ammonia. In certain cases, however, cellular 
wastes remain stored up in the economy, and are rejected only at the 
moment of convalescence; it is under these circumstances that ema- 
ciation is mostly produced after the termination of the disease. 

But we have already stated that all modifications occurring in the 
organism are almost invariably followed by reverse actions. When 
infection is terminated, repair begins and often becomes more active 
than disassimilation had been; hence the notable fattening so fre- 
quently observed. The fact is of common occurrence after typhoid 
fever. Likewise, consumptives, when they are cured, become obese. 

It is well to mention, finally, that under the influence of microbic 
toxines humoral modifications are produced in the organism; germi- 
cidal and antitoxic substances are formed. All these changes must be 
attributed to a nutritive modification; the cells influenced by the 
microbic products react in a new fashion and modify the chemical 
constitution of the humours. 

It is possible at the present day to ally neoplastic with the infec- 
tious process. The influence of tumours upon nutrition is undeniable, 
as is evidenced by the emaciation, which is so marked and rapid. It 
appears even particularly to affect the transformation of nitrogenous 
substances. Rommelaere has insisted upon the diminution of urea, 
which can not be accounted for merely by starvation. His assertion 
has been acknowledged to be exact, but the interpretation is still under 
discussion. 

All the nutritive phenomena which we have thus far studied are 
produced under the influence of external causes ; once established, they 
may be transmitted by heredity. But the disorder is often more 
marked in the offspring than in the parents; the daughter cells, 
younger, and, consequently, more impressionable, exaggerate the nutri- 
tive disorders which external causes had induced in the mother cells. 
In this manner diatheses are developed. 

Diatheses. — The meaning attached to this term has considerably 
varied. Some authorities speak yet to-day of tubercular, syphilitic, 



DISTURBANCES OF NUTRITION 193 

and cancerous diatheses. These expressions are evidently deplorable. 
Tuberculosis and syphilis are infectious; cancer is a disease unknown 
in its essence, but does not enter into the group of diathesis. In order 
to leave to the word diathesis a precise meaning, we must, following 
Dr. Bouchard, define it as a morbid temperament; and this is, by the 
way, its traditional meaning. Hippocrates called diathesis the manner 
of being, and admitted a diathesis of health and a diathesis of sick- 
ness — that is, as we say to-day, a normal temperament and a morbid 
temperament. 

What, then, is temperament? It is the dynamic state of an indi- 
vidual as opposed to the constitution, which is applied to his static 
state or structure. Temperament is the expression of physiological 
activity — viz., nutritive activity. We are thus led to define diathesis 
as a particular mode of nutrition. 

Accordingly, the number of diatheses is considerably reduced. 
With Dr. Bouchard we admit two — scrofulosis and arthritism. 

Scrofulosis corresponds to what was formerly called lymphatic tem- 
perament ; for among the lesions once considered as scrofulous, several 
must in reality be referred to tuberculosis or hereditary syphilis, of 
which, until recent times, all the clinical varieties were not known. 

The scrofulous child has a special appearance, quite easily recog- 
nised. The characteristics are a fine white skin, flabby flesh, long, silky 
eyelashes, and a large and broad nose, punctuated by spots of acne. 
The tonsils are hypertrophied ; the eyelids are often the seat of ciliary 
blepharitis, subacute or chronic. These children are subject to torpid 
and tedious inflammations ; on the skin impetigo is frequent ; on the 
mucous membranes it is a tenacious coryza, rebellious bronchitis, and, 
in little girls, leucorrhcea. On the slightest lesion the lymphatic glands 
enlarge and remain voluminous. Sooner or later these children become 
tuberculous. In some cases the glands are affected; in others, the 
bones, the joints; and yet in others, the lungs themselves, where the 
disease assumes certain peculiar features, described as scrofulous 
phthisis. 

An inquiry into the antecedents of these children shows that their 
parents were in ill health, generally tuberculous, often syphilitic, some- 
times simply weakened or too old. At all events, it is not a microbe, 
but a nutritive disturbance, resulting from various causes, that has 
been transmitted and exaggerated by heredity. Heredity does not, 
however, sufficiently explain all; in many cases, other factors have 
added their pernicious influence : I refer to all bad sanitary conditions, 
life in confined air without sun, confinement to boarding schools, and 
particularly orphanages. From these etiological conditions we may 
draw a good many therapeutical indications. To remedy the scrofulous 



194: INTRODUCTION TO THE STUDY OF MEDICINE 

temperament, the children must live freely in the sun, snbmit them- 
selves freely to the influence of the open air, and particularly sea air; 
moreover, their nutrition should be stimulated by cutaneous excita- 
tions, by the use of certain medicines, like cod-liver oil and iodine, or 
by hypodermic injections of artificial serum. 

By the side of this first diathetic type is to be placed arthritism, 
including herpetism. Quite different in its causes and manifestations, 
arthritism is peculiar to the higher classes, and is observed mainly in 
countries of advanced civilization. It develops progressively under the 
new conditions imposed by civilization, and is intensified from genera- 
tion to generation. Little by little, the cerebral faculties become pre- 
dominant, engaging all the activity of the individual ; nutrition in the 
other parts declines ; hence arthritism has been considered a sluggish- 
ness of nutrition (Bouchard) or, after Dr. Landouzy's expression, a 
bradytrophy. 

Quite different from the scrofulous, an arthritic person is of a nerv- 
ous temperament ; his flesh is firm, his stoutness is greatly variable ; he 
may be lean, dry, or, on the contrary, fat; he is precociously bald; 
his character is sad, but his intelligence generally bright, and some- 
times remarkably so. In youth he is subject to migraine, the first 
visitation of which he will never forget. When a young man, he be- 
comes asthmatic; later, he has attacks of sibilant bronchitis. About 
the age of twenty-five digestive disorders set in; dyspepsia and consti- 
pation often determine hepatic hypertrophy; the fatty acids, produced 
by defective nutrition, are eliminated by the lungs and the skin, com- 
municating to the breath and sweat an odour of offensive character, 
and predisposing to various skin diseases, notably to eczema. The 
disorders of cellular nutrition bring in their train humoral modi- 
fications. Sugar introduced into, or produced within, the organism is 
not consumed; it remains in excess in the blood, and passes into the 
urine, thus giving rise to a special variety of diabetes mellitus — the 
diabetes of the arthritic, a fatty diabetes, which is liable to last years 
without causing notable symptoms. 

Nitrogenous substances are assimilated as poorly as, perhaps even 
more poorly than, carbohydrates; whence result other humoral dis- 
orders, recognised by the presence in the urine of an excess of phos- 
phates, uric and oxalic acids. These various products may even form 
deposits in certain parts of the organism, creating urinary or biliary 
calculi, or developing gout. 

Of course, all these accidents are only exceptionally the lot of the 
same subject; they may alternate, and be replaced in an individual or 
in his family. A gouty father gives birth to a son subject to migraine ; 
another is diabetic; a third asthmatic; yet another develops renal 



DISTURBANCES OF NUTRITION 195 

lithiasis. We have here a series of disorders which, despite their dis- 
parity from a clinical standpoint, are, nevertheless, linked together by 
the fact that all originate from a nutritive disturbance characterizing 
the diathesis. 

In the last place, in distinction from the scrofulous, the arthritic is 
little disposed to tuberculosis. Should the bacillus, perchance, be 
implanted in his organism, the disease assumes a slow, torpid course; 
sclerosis tends to circumscribe the process, thus developing a fibrous 
phthisis, often curable. 



CHAPTER XII 
DISTURBANCES OF NUTRITION (Continued) 

Auto-intoxications under normal conditions — Organs eliminating or transforming 
toxic substances — Poisons normally contained in the tissues, blood, and urine — 
Importance of urinary toxicity— Pathological auto-intoxications— Role of alter- 
ations of the digestive canal, liver, lungs, skin, kidneys, and the nervous sys- 
tem — Auto-intoxications chemically denned. 

The study which we have just made of cellular nutrition must 
be completed by the act which, in the higher beings, terminates 
the series of nutritive mutations — namely, the rejection of the products 
of disassimilation. When this elimination is hindered, the substances 
abandoned by the cells accumulate in the system and engender dis- 
turbances which are often serious and sometimes fatal. The nutritive 
disturbance thus ends in processes of primordial interest in pathology : 
these are the auto-intoxications. 

Auto-intoxications under Normal Conditions 

The toxic substances which, as we have seen, are produced within 
the normal organism as the result of disassimilation and of gastro- 
intestinal fermentation may be eliminated through numerous emunc- 
tories. 

The bile and the gastrointestinal secretions remove certain useless 
principles ; but a part of the products thus rejected are taken up by 
absorption and re-enter the economy. The true emunctories are repre- 
sented by the skin, the lungs, and especially the kidneys. 

Through the shin are eliminated the volatile fatty acids and vari- 
ous autogenous toxic substances; through the lungs escape especially 
water, carbonic acid, and, in a general way, all the volatile substances 
introduced or formed in the economy. 

Most of the solid materials are eliminated through the kidneys, but 

in order that their elimination may take place, they must become 

dialyzable; the nitrogenous products notably must be transformed into 

urea. Now, the cells reject lower oxidized bodies and ammonia, at the 

196 



DISTURBANCES OF NUTRITION 197 

same time that they abandon a certain quantity of urea. The liver 
causes these different substances to undergo the final transformation 
which permits them to dialyze; the liver, then, is the collaborator of 
the kidneys. The result is that its disturbances profoundly modify 
the secretion of the urine; the urea, the true physiological diuretic, 
is replaced by bodies which are eliminated with difficulty, and by their 
passage may even produce lesions in the kidneys. 

In order that the various nutritive phenomena may be regularly 
produced, the intervention of the nervous system, of which we have 
already spoken, is necessary, as is also that of certain organs which 
have the property of regulating cellular nutrition, either by submitting 
the matter to a special elaboration or by supplying the organism with 
an internal secretion. Besides the liver, whose function we have de- 
scribed, we must mention the pancreas, the thyroid gland, the supra- 
renal capsules, the testicles, and the ovaries. 

The extirpation of the pancreas is followed, as Minkowski has 
shown, by the development of a permanent glycosuria and the habitual 
symptoms of lean diabetes (diabete maigre). Experimentation real- 
izes what clinical experience has established. It has been known since 
the investigations of Lancereaux that diabetes characterized by emacia- 
tion is connected with atrophy of the pancreas, and with a sclerosis 
which is often of tubercular origin (Carnot). The pancreas acts, not 
as a digestive gland, but as an organ endowed with an internal secre- 
tion; it thus regulates the secretion, either by governing hepatic gly- 
cogenesis, or, as is stated by Lepine, by destroying the sugar through 
the agency of a glycocolytic ferment. It is probable, however, that 
glycosuria of pancreatic origin is due to some secondary disorders of 
the hepatic functions. Physiology has clearly shown the relations 
existing between the pancreas and the liver in the regulation of the 
glycogenic function. Therapeutics has established that certain dia- 
betics are cured by the administration of hepatic pulp. 

If we now consider another gland, which is also endowed with an 
internal secretion — viz., the thyroid — we see that its total extirpation 
is followed by manifestations no less curious : sometimes tetany de- 
velops, in other cases a very peculiar nutritive disturbance, myxcedema. 
The difference in the symptoms is perhaps explained by the anatomical 
complexity of the thyroid apparatus, which comprises two orders of 
glands : the thyroids and the parathyroids, which are separated or 
united according to the particular animal species. It seems that 
the lesions of the thyroids are generally followed by disturbances of 
slow course, characterized by mucoid infiltration of the tissues, while 
the suppression of the parathyroids seems to be connected with acute 
manifestations. Myxcedema sometimes leaves the intellect intact and 



198 INTRODUCTION TO THE STUDY OF MEDICINE 

at other times induces cerebral apathy or a cretinoid state. This is 
due, according to Brissaud, to the fact that, in the former case, the 
thyroids alone are affected; while in the latter case the whole appa- 
ratus is affected. Be that as it may, the thyroid gland acts by modi- 
fying cellular nutrition, and the disorders occasioned by its extirpa- 
tion are remedied when the patient ingests thyroid glands taken from 
an animal. One must be very circumspect, however, in this medica- 
tion; the ingestion of the thyroid body has produced various acci- 
dents, and in certain cases has caused death. Only small doses must 
be given daily, from 3 to 4 grammes at the most, which must be 
stopped as soon as the first disorders appear, such as trembling or 
albuminuria. 

That the thyroid gland acts on nutrition is well proved by the fact 
that its ingestion gives excellent results in the treatment of obesity, 
at least in certain cases; for the medication does not always succeed, 
which tends to prove that the mechanism of this morbid state is very 
complex. 

Analogous facts have been observed with regard to the suprarenal 
capsule. Lesions of this organ give rise to a particular syndrom — 
Addison's disease — characterized by two principal symptoms : me- 
lanodermia, which is rather dependent upon concomitant lesions of 
the solar plexus, and asthenia — general weakness — decidedly due to 
alteration of the capsules. In fact, it has been shown by certain physi- 
ological researches that the function of these organs is to neutralize 
the toxines which arise during contraction of the muscles. Attempts 
have been made to treat patients suffering from Addison's disease 
in the same manner as in myxcedema — that is, by the use of supra- 
renal capsules; the method is rational, but it has not as yet led to 
very clear results. 

It is a familiar fact that the extirpation of the testicles or ovaries, 
especially when practised on young subjects, is followed by very marked 
nutritive disorders. In the case of a boy, infantile or rather feminine 
forms are preserved; the pilous system remains rudimentary; the 
larynx does not develop; stoutness is very marked. Finally, veteri- 
narians teach us that in castrated horses the brain is smaller than in 
noncastrated horses of the same stature. 

In the case of women, double ovariotomy results in the develop- 
ment of the pilous system, and especially of rapid obesity. Most of 
these disorders are successfully treated by the use of ovarian extracts. 

Thus, the notions recently acquired in reference to the internal 
secretions of various organs and their role in nutrition have led to a 
new system of therapeutics — opotherapy — of which Brown-Sequard 
was the pioneer. 



DISTURBANCES OF NUTRITION 199 

Toxic Substances of Normal Tissues of the Blood and Urine. — 
The second stage of nutrition, disassimilation, results in the introduc- 
tion into the blood of a certain quantity of useless and harmful waste 
products. Thus it has been possible to say that, even normally, the 
organism is a receptacle and a laboratory of poisons (Bouchard). All 
parts of the body contain some posions. These are, first, the tissues, 
the extracts of which prove rapidly fatal when injected into the veins. 
In making cold macerations of the liver or muscles in salt water, it is 
found that in order to kill 1 kilogramme of animal the extract of 14 
to 20 grammes of liver or 90 to 95 grammes of muscle must be in- 
jected into the veins. The greatest part of the toxicity depends upon 
albuminoid matter; and hence the extracts prepared hot are far less 
toxic. In order to kill 1 kilogramme, the extract of 117 grammes of 
liver or of 216 grammes of muscle must be introduced. 

The substances thus entering into the constitution of the tissues 
pass into the blood more or less modified, but they only traverse this 
liquid. Hence the blood has very little, if any, toxicity, at least when 
it is transfused between animals of the same species ; for the blood or 
the serum of one species is toxic for animals of different species. In 
operating on rabbits, it has been possible to determine in the following 
way the toxicity of the serum — viz., the amount necessary for killing 
1 kilogramme of animal by intravenous injection : * 

Horse serum 80 cubic centimetres. 

Chicken serum 20 

Calf serum 13 

Human serum 10 

Cattle serum 8 

Eel serum 0.05 

Now that therapeutics has so often recourse to serum injection 
these facts have a practical interest. It should be noted, however, that 
the results are not similar in man and in the rabbit. Horse serum, 
so well supported by the rabbit, produces in man numerous disturb- 
ances even in minute doses: arthropathies, fever, erythemata, albu- 
minuria. On the contrary, the cattle serum, five to ten times more 
toxic for the rabbit, seems to be better borne by man. Dr. Beclere has 
proved its innocuousness by injecting smallpox patients with the serum 
of vaccinated calves in doses as high as one fortieth of the body 
weight. 

This toxicity of the serum it is very important to know; but we 

* In all these experiments the injections were made into rabbits by the intra- 
venous route. All the results are based on the scale of the animal kilogramme, 
and the figures are obtained by dividing the dose which proved fatal by the weight 
of the rabbit. 
14 



200 INTRODUCTION TO THE STUDY OF MEDICINE 

are not concerned with its study, for it is a question of the action of 
albumins of the foreign blood, albumins which evidently are not toxic 
for the animal from which they are derived. As to the true poisons, 
they should be looked for, not in the blood, where they do not so- 
journ, but in the fluids through which they are eliminated. From 
this point of view, it is the urine that has been most often studied. 

Urinary Toxicity. — The brilliant researches of Feltz and Bitter, 
and especially those of Dr. Bouchard, have finally established that the 
urine contains numerous toxic substances to which three sources may 
be assigned: alimentation, gastrointestinal fermentation, and disas- 
similation. 

In order to determine the toxicity of a urine, the whole amount 
passed in twenty-four hours is collected. The liquid having been 
filtered, it is then injected into a rabbit through a peripheral vein 
and at a uniform rate. When the animal is dead the amount of urine 
introduced is noted and the figure obtained is divided by the weight of 
the animal ; thus is determined the dose fatal for 1 kilogramme. This 
is what is designated as a urotoxia. 

On an average, a man eliminates in twenty-four hours 1,200 cubic 
centimetres of urine, the toxicity of which is 40 cubic centimetres per 
kilogramme; the total urine kills ^f-^- — that is, 30 kilogrammes; 
therefore it represents 30 urotoxias. 

If the man weighs 65 kilogrammes, a very simple calculation shows 
that in fifty-two hours he eliminates an amount of poison sufficient to 
kill his own weight. In twenty-four hours 1 kilogramme of this man 
eliminates an amount of poison which would poison 0.460 kilo- 
gramme. This is the urotoxic coefficient, which is obtained by divid- 
ing the number of urotoxias passed in twenty-four hours by the weight 
of the individual; the average of numerous experiments made from 
this point of view has given the figure 0.461 kilogramme. 

The substances which give the urine its toxicity are not well known 
from a chemical point of view. It is only known that there exist a 
mineral toxic matter (potash), toxic colouring substances, and poisons 
similar to ptomaines ; it is also known that separation can be secured 
by means of solvents, such as alcohol, ether, or chloroform, or else 
through dialysis. It has thus been possible to determine that the 
urine contains at least ten toxic substances, which are well character- 
ized by their action on animals : 

1. A diuretic substance, of little toxicity, even of some value, since 
it assures diuresis — viz., urea. 

2. A narcotic substance, soluble in alcohol. 

3. A sialagogue substance, equally soluble in alcohol. 

4. A convulsive mineral substance, potash. 



DISTURBANCES OF NUTRITION 201 

5. A convulsive organic substance, which is precipitated by alcohol. 

6. A miotic substance, insoluble in alcohol. 

7. A hypothermizing substance, which is not dialyzable. 

8. A thermogenic substance, which is dialyzable. 

9. A mineral poison, potash, arresting the heart. 

10. An organic poison arresting the heart. 

The toxicity of the urine resulting from these diverse poisons 
varies considerably even under physiological conditions. It is possi- 
ble, in the first place, to restrain it by modifying alimentation, chiefly 
by diminishing the potash salts; by a milk diet, and, according to 
Marette, especially a diet composed of milk and rice notably dimin- 
ishes the urinary toxicity. On the other hand, we may obtain a similar 
result by favouring oxidation, either by submitting the subjects to the 
action of compressed air or by causing them to take moderate exer- 
cise. If, however, muscular work is pushed to the point of fatigue, 
cellular waste increases in great proportion and renders the urine very 
toxic. The examinations which have been made after long rides on the 
bicycle leave no doubt in this respect. In the experiments of Drs. 
Tissie and Sabrazes, the urotoxic coefficient in individuals who took 
part in the run from Paris to Bordeaux reached 2.35, which was five 
times greater than the normal. 

Without dwelling on the toxicity of other organic secretions, we 
shall only remark that the bile is toxic in doses of 4 to 6 cubic centi- 
metres per kilogramme; that the gastric juice, the pancreatic juice, 
and the sweat also give rise to disturbances when they are injected 
into the veins. Finally, according to Brown-Sequard and d'Arsonval, 
the expired air contains a poison similar to volatile ptomaines. Al- 
though it has been contradicted, this last result is interesting; it ex- 
plains the noxious effects of confined air. 

Now that we are acquainted with the toxic substances which are pro- 
duced under normal conditions, it will be easy to understand what 
occurs in pathological states. 

Pathological Auto-intoxications 

The digestive canal represents the principal apparatus for the pro- 
duction of auto-intoxication. The fermentations occurring therein are 
exaggerated under a great number of circumstances; in others, the 
toxines produced are not completely eliminated. Whether it be an 
attack of indigestion, dyspepsia, or a case of dilatation of the stomach, 
whether diarrhoea, constipation, or even intestinal obstruction be pro- 
duced, the results are the same. An auto-intoxication is induced, 
attended with numerous disturbances to which we have already re- 
ferred when speaking of digestive fermentations. There are headache, 



202 INTRODUCTION TO THE STUDY OF MEDICINE 

weakness, a general exhaustion, sometimes more serious disorders, such 
as aphasia; and, lastly, two phenomena which have recently been well 
studied, tetany and diaceturia. 

Tetany, to which we have already referred in speaking of the thy- 
roid gland, is generally observed in cases of hyperchlorhydria. Hydro- 
chloric acid, when produced in excess, gives rise in nitrogenous matter 
to the development of toxic substances which Bouveret, Devic, and 
Gassaet have isolated. The disturbances have nothing special from a 
symptomatic point of view, but they are very often grave and have 
sometimes caused death. 

Diaceturia is also a phenomenon of a toxic order, giving rise to a 
very serious syndrome — namely, dyspeptic coma. We shall again refer 
to it when speaking of auto-intoxications of diabetic origin, where 
diaceturia is of more frequent occurrence. 

Auto-intoxications of Hepatic Origin. — The production of poisons 
being normal or exaggerated, disturbances may occur as the result of 
some derangement of the organs which neutralize or eliminate toxic 
substances. 

To the first group belongs the liver, which arrests, transforms, and 
neutralizes the substances brought to it by the portal vein. When the 
hepatic cells are altered, this protective role is diminished and some- 
times even abolished. 

We can recognise the power of the liver by several procedures. 
Numerous experiments have demonstrated that the various functions 
of the hepatic cell are united, interdependent: when one is disturbed 
the others are affected. At the same time that the liver ceases to 
arrest the poisons it no longer elaborates the biliary pigments in a 
normal manner and urobiline is found in the urine. It no longer acts 
on the nitrogenous matter, and the amount of urea is diminished, 
or at least the proportion between the nitrogen of urea and the total 
nitrogen ; albuminuria and peptonuria may be produced. But, chief of 
all, the liver ceases to retain the carbohydrates, and sugar passes into 
the urine when the portal vein contains an excess of it — that is, after 
meals — and alimentary glycosuria follows. The patient is given in the 
morning, before breakfast, 150 to 200 grammes of sirup; then the 
urine voided during the following four or five hours is collected ; if the 
liver is normal, no glucose is found; if the glycogenic function is dis- 
turbed, glucose will pass into the urine. But several conditions may 
interfere with the results. Although the liver may be insufficient, gly- 
cosuria may not make its appearance, either because the intestinal 
absorption is hindered or because the capacity of the cells for con- 
suming sugar is increased, or, finally, because the renal emunctories are 
not performing their work normally. 



DISTURBANCES OF NUTRITION 203 

We may also determine the state of the liver by studying the 
elimination of various substances which this gland retains, at least 
partially, under normal conditions. Thus it is possible to investigate 
the manner in which the urine excretes the quinine salts, and espe- 
cially how the lungs eliminate sulphuretted hydrogen. The latter 
method has been employed thus far on animals only, but it has already 
afforded valuable information. It suffices to inject a certain amount 
of a solution of sulphuretted hydrogen into the rectum; the liver 
arrests this gas ; but, if this organ is altered, more or less considerable 
quantities pass into the expired air, where it is easily detected by means 
of lead-acetate paper placed before the nostrils. 

A procedure that gives good results, but which, unfortunately, is 
not practical, is the study of urinary toxicity. Researches pursued in 
this direction have demonstrated that, if the antitoxic power of the 
liver is preserved, the urine, even when charged with biliary pigment, 
is not more toxic than normally. When the cells are profoundly 
affected, the urine contains from four to five times more poisons; at 
least that is what occurs when the kidneys are permeable. If these 
glands are altered, the poisons are retained in the organism and quickly 
bring about a fatal termination. 

The fact that the urinary toxicity always increases whenever ali- 
mentary glycosuria exists further demonstrates the correlation exist- 
ing between the different functions of the liver, notably between the 
glycogenic and the antitoxic action. 

These physiological data in the role of the liver in intoxications 
find numerous applications; they explain one of the most interesting 
syndromes of pathology — namely, icterus gravis. 

Under this name is described a complex morbid state, including 
three varieties, according as it may be a question of an infectious, a 
toxic, or a dystrophic process. 

Infectious icterus gravis may be due to the most common microbes 
— streptococcus, and particularly the colon bacillus. It is observed in 
young subjects, sometimes in epidemic form, and in soldiers after 
overexertion. It may also occur in individuals exposed to mephitic 
vapours, or who have inhaled sewer gas, or have worked in the soil. 
In women, pregnancy and the puerperium represent indisputable predis- 
posing causes. The disease is essentially characterized by the occur- 
rence of an always serious icterus with fever, accompanied by disorders 
of the nervous system and hemorrhages, which indicate the profound 
intoxication of the organism. The first clinical form of icterus gravis 
is often cured, generally after a urinary crisis — i. e., a sudden increase 
of the renal secretion, which throws out the poisons accumulated dur- 
ing the course of the disease. 



204 INTRODUCTION TO THE STUDY OF MEDICINE 

A second variety of icterus gravis is that which is induced by poi- 
sons capable of provoking degeneration of the hepatic cells, of which 
phosphorus is an example. 

Lastly, the third group comprises the secondary forms of icterus 
gravis, which terminate the evolution of the various affections of the 
liver — cirrhosis, hydatid cyst, cancer, and passive congestion of the 
liver. Disturbances which rapidly grow worse are developed, such 
as hemorrhages and nervous manifestations, and the individual finally 
succumbs to hepatic insufficiency. 

These three varieties, while quite distinct from an etiological stand- 
point, are similar in their clinical manifestations. In fact, they are 
all due to the same process. All the causes which we have mentioned 
induce degeneration of the hepatic cells. Although the point of de- 
parture is different, the results are alike; the process is always de- 
pendent upon suppression of the functions of the liver. 

It is therefore at present easy to explain the mechanism of icterus 
gravis. The ancient theory which assumed the passage of the bile 
into the blood is no longer tenable, for no one would be able to under- 
stand why mild icterus should exist. The idea of Frerichs, who sup- 
posed an accumulation within the organism, not of the bile, but of 
products which were to be elaborated in the liver for its formation, is 
not supported by conclusive proof. Impressed with the inadequacy 
of the hepatic theories, Whitla and Decaudin have attributed the prin- 
cipal role to concomitant alterations of the kidneys. There is some 
truth in this view. It is certain that in persons suffering with 
Bright's disease, all cases of icterus are of a very serious prognosis. 
Nevertheless, there are cases in which the kidneys are permeable, and 
yet accidents occur. The principal role, therefore, is to be attributed 
to hepatic disorders. But it is not in the bile-producing function of 
the liver that an explanation of the disturbances is to be found, it is 
rather in the study of its antitoxic function. When the cells have 
become insufficient, the numerous toxic substances which should be 
retained and annihilated by the liver pass freely through the gland 
and impregnate the system. Icterus gravis may therefore be defined 
as an auto-intoxication dependent upon insufficiency of the liver. 
It is conceivable that the most varied causes may give rise to this 
syndrome; all that is necessary is the production of a diffuse degen- 
eration of the hepatic cells. 

Auto-intoxications of Pulmonary, Cutaneous, and Renal Origin. — 
In addition to the liver, various glands are charged with the duty of 
preventing the intoxication of the organism. We have already indi- 
cated the role of the thyroid gland and of the suprarenal capsules. We 
shall now consider the organs concerned in the elimination of poisons. 



DISTURBANCES OF NUTRITION 205 

The lungs and the skin belong to this group. The action of the 
lungs, however, is much more important than was once believed. At 
the present day it is known that the lungs not only eliminate volatile 
substances, but neutralize alkaloids, such as nicotine, the sulphates of 
strychnine and atropine, organic acids, and salts, such as arsenite of 
potash. Their action is not exercised unless respiration be normal. 
The process is probably one of oxidation. 

The skin seems to eliminate volatile substances only. When the 
exhalation of the skin is suppressed, as is the case when the body of an 
animal is varnished, death supervenes in coma accompanied by a fall 
of temperature, scanty urine, albuminuria, and sometimes hematuria. 
The effects are the same when an extensive, even though superficial, 
burn abolishes the action of the skin, or when the integument is the 
seat of extensive dermatoses. 

The kidneys also come to the assistance of the organism. To a 
certain extent they can make up for the cutaneous as well as for the 
hepatic insufficiency, and eliminate the excess of poisons. But, finally, 
in consequence of the excessive work imposed on them, or as the result 
of the continual passage through them of anomalous substances, they 
in turn become altered and incapable of depurating the organism. 
Then a new syndrome develops — namely, uraemia. 

Urcemia is to the kidney what icterus gravis is to the liver. It 
is a syndrome resulting from an auto-intoxication dependent upon 
renal insufficiency, which, of course, means that this morbid state may 
appear under the most dissimilar conditions, such as occur during the 
course of infections, intoxications, whether of exogenous or endogenous 
origin, and all processes capable of altering the epithelia of the 
kidneys. 

The mechanism of uraemia has long been a subject of discussion. 
It was once attributed to the systemic accumulation of urea ; but this 
substance, on the contrary, far from being toxic, serves to assure diu- 
resis, and its subcutaneous introduction gives good results in the treat- 
ment of certain cases of renal insufficiency. Urea being easily trans- 
formed into ammonium carbonate, this salt was next looked upon as 
the causative factor. This theory contans a great deal of truth, but 
it appears to be too exclusive. In reality, uraemia is a complex intoxi- 
cation, due to the retention of various poisons the presence of which 
in the urine has been demonstrated by experimental analysis. But we 
can understand that according to the nature, extent, and profundity 
of the renal alterations certain substances may be able to traverse the 
filter and that others may be retained. Probably this explains 
the diversity of the disturbances and the variability of the clinical 
manifestations, which have been grouped under three principal heads, 



206 INTRODUCTION TO THE STUDY OF MEDICINE 

according as nervous, gastrointestinal, or dyspnoic phenomena pre- 
dominate. 

It would not, however, be proper to simplify the theory too much, 
or to imagine that uraemia is due to retention of urine, or that 
intravenous injection of this liquid produces in animals disturb- 
ances identical with those observed in man. In reality, the facts are 
more complex. The urinary poisons stored up gradually act upon the 
nutrition of the cells. Accumulating in the blood and the tissue 
fluids, they completely modify nutritive exchange. What proves this 
is that the blood serum contains albuminoid substances which differ 
in their toxic properties from those which are normally found there. 
In fact, it has been recognised that the blood of uraemic subjects is 
very toxic for the rabbit. This result does not at all demonstrate the 
accumulation of substances which should be eliminated by the urine, 
for the toxicity of the serum depends upon albuminoid substances — 
namely, substances which are not at all concerned in urinary toxicity. 
This, however, is not a sufficient reason to deny the accumulation of 
urinary poisons within the organism, for this secretion is very slightly 
toxic in cases of renal insufficiency; we mean that only these poisons, 
once retained, induce profound modifications in the elaboration of 
albuminoid matter. 

Insufficiency of the liver and, secondarily, of the kidneys also 
explains the development of puerperal eclampsia. The presence of 
albumin in the urine of a pregnant woman often enables us to foretell 
the imminence of this formidable manifestation. The study of the 
serum establishes that this liquid is very toxic and can kill in minute 
doses of from 3 to 6 cubic centimetres. This toxicological research 
is not merely of speculative interest. Experience demonstrates that 
the prognosis remains good, despite the gravity of the symptoms, 
when the serum is feebly toxic. On the other hand, a very toxic 
serum must lead to a grave prognosis, even though the symptoms 
be mild. 

Auto-intoxications in Nervous Affections and Infections. — Ex- 
tremely interesting researches have also been pursued in connection 
with auto-intoxication in mental affections. As a rule, the toxicity of 
the urine is increased, and sometimes it presents particular character- 
istics connected with the state of the patients. According to Brugia, 
the urine of excited persons is convulsive, while that of depressed 
individuals produces prostration and considerable hypothermia. Fi- 
nally, turning his attention to a paroxysmal disease — viz., epilepsy — 
Dr. Fere established that the urine, which is very toxic and strongly 
convulsivant before an attack, afterward becomes feebly toxic and 
slightly convulsivant. 



DISTURBANCES OF NUTRITION 207 

The study of infectious diseases has particularly given rise to 
numerous researches. We have already said that intoxication plays 
the principal part in all infections. Toxic substances are referable to 
three sources: Some are produced by the pathogenic agent; others 
are derived from gastrointestinal fermentations, generally increased; 
and still others are due to exaggerated or perverted cellular disassimi- 
lation. If we remember that in every infectious disease there is an 
alteration of the glands charged with the destruction or elimination of 
poisons — that the liver, the kidneys, the thyroid gland, the supra- 
renal capsules, and the skin are more or less affected — we must 
conclude that all work together to prevent the depuration of the 
organism. 

The disorders in the elaboration of the materials of nutrition affect 
the composition of the urine, which is found to contain extractive 
matters and amido acids in excess, and often anomalous substances, 
such as serine, globulines, and albumoses. It is probable that the tox- 
icity so marked in the blood and urine is due to modification of albu- 
minoids. Even injected into beings of similar species, the urine de- 
rived from infected animals causes death in minute doses of from 10 
to 15 cubic centimetres. By injecting into rabbits the serum of indi- 
viduals suffering from pneumonia, Eummo and Bordoni found that 
instead of 10 cubic centimetres, which is a fatal dose under normal con- 
ditions, the toxicity is from 5 to 6 cubic centimetres, and before defer- 
vescence may reach 0.8 cubic centimetre. In studying the serum of 
typhoid patients, the same authors observed that the fatal dose, which 
varies within normal limits during the first week of the disease, rises 
during the second week to a point represented by 2 cubic centimetres 
and even 1 cubic centimetre ; then it diminishes, and is again reduced 
to its usual figure during the following week. 

The variations in the toxicity of the urine are not necessarily par- 
allel with those of the toxicity of the serum. As a rule, they follow 
reverse directions. An especially striking example is seen in pneu- 
monia; while the serum becomes more and more toxic as the disease 
advances, the toxicity of the urine diminishes. On the eve of the 
crisis it falls to its minimum, then it abruptly rises. Therefore we 
may suppose that during the course of the disease nondialyzable sub- 
stances accumulate in the economy and impart to the blood its tox- 
icity. At the moment of convalescence these probably undergo a trans- 
formation, rendering them dialyzable ; there must be produced a dislo- 
cation of very unstable albuminoids, which fact explains why there are 
found in the urine ptomaines, which certainly are derived from the pri- 
mary poison, the presence of which in the blood is demonstrated by 
experiment. 



208 INTRODUCTION TO THE STUDY OF MEDICINE 

Auto-intoxication chemically defined. — Parallel with the auto-intox- 
ications which we have thus far studied, and in which the complex 
phenomena are due to various chemically ill-defined poisons, must be 
placed those intoxications due to well-determined substances. 

We shall note lacticasmia — i. e., the accumulation of lactic acid in 
the blood. It occurs when oxidation is hindered — e. g., in asphyxia, 
infectious diseases, and poisonings by phosphorus and carbonic oxide ; 
it may also be observed in gastrointestinal affections and in diabetes, 
where lactic acid is found associated with diverse organic acids. This 
excess of acids in the blood explains the pains in the bones of dia- 
betics, and it also accounts for rickets induced by gastrointestinal 
disorders. 

In speaking of digestive auto-intoxication we noted a special syn- 
drome — i. e., the dyspeptic coma related to diaceturia. This syndrome 
is chiefly observed in diabetics, and particularly in those who, on the 
advice of their physician, eat too much meat. We then observe the 
various phenomena characterizing this morbid state, occurring in most 
cases in consequence of fatigue or a journey. At all events, the symp- 
toms are very simple and three in number : a sharp pain in the epigas- 
trium ; a progressive obnubilation, terminating in coma ; a respiratory 
type, designated Kussmaul's coma, characterized by breathing divided 
into four periods — a brisk inspiration, a pause, a brisk expiration, and 
a pause. Along with these disorders, or prior to their appearance, a 
characteristic phenomenon is produced — that is, a special odour ex- 
haled by the breath and urine of the patient — a strong odour recalling 
that of chloroform. It is attributed to acetone, whence the name ace- 
tonemia or acetonuria, often given to the syndrome. But if acetone is 
in fact produced under these circumstances, the disturbances are rather 
attributable to a similar body, ethyldiacetic or acetylacetic acid. It is 
this acid that is brought to light by the following test, which should 
always be resorted to in these cases : The urine being placed in a test 
tube, a few drops of perchloride of iron are poured along the side of 
the tube. The iron, by virtue of its density, falls to the bottom of the 
test tube, and if ethyldiacetic acid exists, the perchloride assumes a 
brownish-red colour, resembling that of Bordeaux wine. The reaction 
is not absolutely characteristic, for it is also produced when the pa- 
tient has ingested antipyrine. This source of error, however, is easily 
eliminated. 

Apart from ethyldiacetic acid, the urine contains other acids, such 
as lactic and ^-oxybutyria acids. This led to the belief that it would 
be possible to prevent accidents by neutralizing these acids, by intra- 
venous injections of solutions of sodium bicarbonate. The attempt 
was rational, but it has as yet given no results. 



DISTURBANCES OF NUTRITION 209 

Aside from diabetes, diaceturia may be produced in the following 
conditions : In persons subsisting on a meat diet ; in certain forms of 
dyspepsia, where it engenders coma similar to diabetic coma, but dif- 
fering from the latter by the absence of KussmauFs respiration ; in the 
course of certain infections, and in asphyxia. 

Among other chemically denned auto-intoxications must be men- 
tioned that caused by uric acid, which is derived from nuclein — that 
is, from cellular nuclei. The excessive production of this agent gives 
rise to the development of gout. We must also mention ammoniacal 
intoxication, which occurs in infectious diseases, and especially in 
affections of the digestive canal and of the liver; intoxication by 
anomalous albumins and the albumoses, which are produced under a 
great number of circumstances already referred to; intoxication by 
ptomaines, the genesis of which we have pointed out; and, finally, 
intoxication by volatile substances originating in the alimentary canal 
— sulphuretted hydrogen and methylmercaptan. 

If we consider the numerous data furnished by the study of au- 
togenous poisons, we see that the living organism is always in danger 
of intoxication, even under normal conditions. In diseased states poi- 
sons increase because new substances are produced by pathogenic 
agents, gastrointestinal putrefaction is exaggerated, and cellular dis- 
assimilation is more active and often deviates from the normal type. 
These chemically ill-defined poisons have been well studied experi- 
mentally. Moreover, it has been established that the organism pos- 
sesses several means of protection against them; it transforms and 
eliminates them and produces antitoxic substances which counter- 
balance and neutralize their effects. When one of the protective organs 
is attacked, others replace it; for instance, the liver and kidneys can 
replace each other to a certain extent. 

This study of auto-intoxications has demonstrated that numerous 
morbid phenomena originate within the organism. There is no excep- 
tion here, however, to the rules already laid down. In fact, the dis- 
turbances are secondary, and always referable to an external cause. 
There are thus produced, directly or indirectly through the nervous 
system, cellular disorders, which secondarily give rise to humoral modi- 
fications. These derangements and modifications may be transitory, 
or they may become permanent ; in a great number of cases they may 
be transmitted to descendants. We are thus led to the study of the 
pathology of the foetus and of heredity. 



CHAPTER XIII 
PATHOLOGY OF THE FCETXJS— HEREDITY 

Pathology of the foetus— Passage of toxic substances and of microbes through 
the placenta— Congenital infections— Malformations— Transmission of certain 
acquired characters— Heredity— Influence of each generator— Consanguineous 
marriages— Maternal impregnation— Atavism— Heredity of nutritive disor- 
ders: diathesis— Heredity in toxic and infectious diseases— Nervous heredity- 
Superior and inferior degenerates— Genius, insanity, crime — Conclusions. 

Although protected in the uterine cavity, the foetus is not entirely 
beyond the reach of external agents. It may suffer traumatism; it 
may be exposed to the influence of the surrounding modifications of a 
physical order; it may be assailed by toxic substances or animate 
agents entering through the only channel which connects it with the 
external world — through the placenta and the umbilical vein. Diseases 
or lesions may thus be produced which must be considered as congeni- 
tal and not hereditary. 

Intoxications. — The passage of toxic substances from the mother 
to the foetus has been repeatedly studied. Since the old experiments 
of Mayer (1817) and Albers (1859) and those of Dr. Porak, a great 
many facts have been discovered throwing new light upon the question. 
We now know that lead, arsenic, the iodide and bromide of potassium, 
and phosphorus may pass through the placenta. The last-named sub- 
stance at times produces placental hemorrhages and causes a charac- 
teristic fatty degeneration in the liver of the foetus. Iron and mercury 
do not pass from the mother to the foetus, although mercury accumu- 
lates in the placenta. Most of the colouring substances do not impreg- 
nate the foetus; yet Flourens observed that the bones and teeth were 
red in a pig whose mother had ingested madder during gestation. 
The intraplacental transmission of alkaloids, opium, atropine, quinine, 
etc., is generally conceded to-day. 

Certain clinical and experimental facts also prove that carbonic 
oxide may reach the foetus; but the quantity contained in its blood 
is six times less than that found in the mother. This proportion, more- 
210 



PATHOLOGY OF THE FGETUS— HEREDITY 211 

over, expresses a general law : Weights being equal, the foetus contains 
a less amount of toxic substances than the mother, and its tissues 
offer a much greater resistance to intoxication. Living foetuses have 
been extracted from the uteri of women and animals killed by chloro- 
form, chloral, or asphyxiation. A very interesting experiment by 
Savory positively established this fact : If one of the foetuses be ex- 
tracted by laparotomy from the uterus of a pregnant female and be 
returned to the womb after having received a strong injection of 
strychnine, fatal convulsions will be produced in the mother in con- 
sequence of the passage of the alkaloid from the foetus to the mother 
through the placental circulation. The foetus is in no way affected, 
and, if sufficiently developed, a Cesarean operation may save it. It 
withstands, then, a much stronger dose of strychnine than suffices to 
kill the mother. The foetus may die in a case of poisoning, but its 
death is then brought about by the fall of blood pressure in the 
mother. 

Let us now consider the organs qualified to protect the foetus 
against poisons. As poisons are always brought in by the umbilical 
vein, they first travel through the liver. This organ acts as in the 
adult; it arrests and destroys the toxic substances, provided it contains 
glycogen. Now, the researches of Claude Bernard have shown that 
glycogen exists in the embryo at first only in a diffused state, and 
that it is only from the second half of gestation onward that it 
localizes itself in the liver; it is from this period that this organ 
exerts its protective functions. 

The poisons not destroyed by the liver leave the foetus by the 
umbilical artery and the placenta, and in this way return to the 
mother. It has been said that they are also eliminated by the kidneys. 
The experiments of Dr. Porak, however, do not confirm this assertion ; 
the amniotic fluid does not contain the substances absorbed. If sali- 
cylate of sodium be given a few hours before parturition, no trace of 
the substance can be found in the urine of the newborn. Therefore 
it may be stated that renal elimination begins at birth and becomes 
effective only at the end of a few days. 

Infections of the Foetus. — Do microbes, like poisons, pass through 
the placenta ? The answer is not a matter of doubt ; the existence of 
congenital smallpox and syphilis is an incontrovertible demonstration 
of the passage of microbes from the mother to the product. 

The memorable experiments of Pasteur on silkworms furnish very 
interesting results in this connection. Two diseases exist among silk- 
worms, pebrine and flacherie. The germs of pebrine may pass from 
the mother to the eggs and to the young; the male does not transmit 
the disease, but produces a debilitated progeny. In flacherie, on the 



212 INTRODUCTION TO THE STUDY OF MEDICINE 

contrary, neither the male nor the female can transmit the infection; 
but if one of them has contracted the disease, the offspring is weak and 
evinces a well-marked tendency to acquire the disease. 

Analogous facts are observed in man and in mammals. The first 
experimental researches, in this case as in all the others, were under- 
taken with anthrax. Brauell and Davaine, the experimenters who 
began the study of the question, obtained negative results only, and 
affirmed that the placenta is a perfect filter. This law of Brauell- 
Davaine is false, as Straus and Chamberland have shown. But the 
number of bacilli which pass through the placenta is minimal, and 
microscopic observation does not suffice to reveal their presence ; only 
cultures made with large quantities of liver will do so. In this manner 
positive results are obtained in about half the cases. The problem as 
to the cause of these inconstant results has been taken up by Dr. Mal- 
voz. According to this author, the Bacillus anthracis passes through 
the placenta only when this organ is altered. The problem, therefore, 
as to what are the causes of the localization of microbes in the pla- 
centa as well as in other organs resolves itself into a much wider ques- 
tion, and one which we can not satisfactorily solve, although we have 
some data bearing upon it. However this may be, the results are 
identical in man. In four published observations the foetus of a 
mother suffering from anthrax twice contained the bacterium (Mar- 
chand, Paltauf), twice it did not (Eppinger, Morisani). 

Among the other microbes which may produce foetal infection may 
be cited the pneumococcus, which may cause a much more serious dis- 
ease than in the mother. In an observation of Thorner, a woman was 
delivered the day after the defervescence of a pneumonia; the child 
died thirty-six hours later. The autopsy revealed hepatization of the 
lower lobe of the left lung and the presence of pneumococci. better 
has reported a case of congenital infection in which pneumococci in- 
vaded the lungs, the pleura, and the meninges. 

Relatively numerous observations establish that the bacillus of 
Eberth may pass through the placenta; but it does not produce any 
lesion in the foetus, no alteration of Peyer's patches, and no splenic 
hypertrophy. It causes a true septicaemia. 

It is different with smallpox. There are on record a certain num- 
ber of observations of congenital smallpox in which the child came 
into the world with the pustules characteristic of the disease. In 
most cases it had not advanced so far in the child as in the mother. 
This proves that their infection had not been simultaneous. It goes 
without saying that contamination is not a constant occurrence; in 
twin birth one of the children has been known to be affected and the 
other not. Finally, vaccinated women living in an epidemic centre, 



PATHOLOGY OF THE FCETUS— HEREDITY 213 

without being themselves affected, have given birth to children covered 
with pustules. 

The other eruptive fevers are also observed in the foetus, but only 
exceptionally. 

The transmission of various infections, such as glanders, hydro- 
phobia, cholera, and paludism, has also been observed. Although very 
interesting, these facts add nothing new to the history of congenital 
infections. On the other hand, highly important results have accrued 
from the study of two chronic infections — namely, syphilis and tuber- 
culosis. While the preceding diseases have a rapid evolution and can 
be communicated only by the mother, in syphilis and tuberculosis the 
influence of both parents must be taken into account. 

Hereditary Syphilis. — When the mother is syphilitic, there are sev- 
eral possibilities. In certain cases placental lesions exist and bring 
about abortion. The frequency of this occurrence is well known; and 
repeated abortions, if otherwise unexplained, must always suggest 
syphilis. In other cases the child is born with specific manifestations 
upon the skin and mucous membranes. A third class of facts is made 
up of those in which the child, normal at birth, shows syphilitic affec- 
tion toward the sixth week; various eruptions appear, particularly 
blebs of pemphigus, which, when located upon the soles of the feet, are 
absolutely characteristic. But the specific lesions may appear much 
later — for example, after fifteen or twenty years. This is what is 
known as retarded hereditary syphilis. 

When the father alone is syphilitic, the same possibilities exist, and 
abortions are particularly frequent. But, what is more remarkable, the 
foetus may be syphilitic while the mother remains sound. Neverthe- 
less, in such cases the maternal organism is altered, since it has 
acquired immunity from syphilis. This is known as the law of Colles, 
which, from a practical standpoint, may be expressed as follows: A 
woman who has been delivered of a syphilitic child, if she remains 
unaffected, can suckle her nursling without exposing herself to con- 
tamination. 

Several hypotheses have been advanced to explain this immunity. 
It has been maintained by some that a uterine chancre existed and 
passed unnoticed. If this were the case the immunity would be due 
simply to an infection. In support of this theory the unique obser- 
vation of Lewis is cited: A woman is fecundated by a syphilitic and 
gives birth to a contaminated child; she remains intact. Subse- 
quently she is impregnated by a healthy man and conceives another 
child, also syphilitic. Here is proof that the unknown microbe of 
syphilis had invaded the maternal organism. It is true that this fact 
admits of another explanation and could just as well be looked upon 



214 INTRODUCTION TO THE STUDY OF MEDICINE 

as an instance of conceptional syphilis. Under this name are grouped 
those cases in which the organism of a woman bearing a syphilitic 
foetus is from the first invaded by the virus and a general infection 
occurs without primary lesions, but which is immediately expressed by 
secondary manifestations. In this case it is the microbe which has 
passed through the placenta from the foetus to the mother. When 
immunity alone is transmitted, it is generally admitted that only the 
soluble substances, and not the figurate elements, have traversed the 
filter and have conferred upon the mother a marked power of resist- 
ing infection. 

When the parents are not syphilitic and the mother contracts the 
disease during pregnancy, two results are possible: If contamination 
takes place before the seventh month, the chances are that the foetus 
will be infected ; after that time it will remain sound ; and this is easily 
understood, since the infection has not had time to spread, because it 
is still local. 

If a child born of a syphilitic mother manifests no trace of infec- 
tion at birth, it may be suckled by its mother without danger. It has 
acquired immunity. This is the law of Profeta, which may be placed 
by the side of the law of Colles. 

Hereditary Tuberculosis. — The observations made upon hereditary 
syphilis have been turned to account in the study of tuberculosis. At 
the present day it is an incontestable fact that tuberculosis is very fre- 
quent in early childhood. Dr. Landouzy, who has clearly brought this 
fact to light, is of the opinion that half the cases of death in newborn 
children are caused by this infection. Although an agreement has 
been reached on this first point, the operating mechanism is still a 
subject of contention. According to some, it is the germ which is 
transmitted; according to others, it is only a predisposed organism — 
the soil. In other words, the child may be born tubercular or with 
a tubercular tendency. 

Incontrovertible, if not numerous, instances in which tubercles con- 
taining the characteristic microbe were found in stillborn children 
have been cited in favour of intraplacental transmission. In some 
cases the lesions predominate in the liver, which is the first organ 
reached by the bacilli coming from the placenta. 

Analogies derived from syphilis have led to the admission that the 
microbe may remain inactive in some corner of the organism — in the 
marrow of the bones, for instance — and become active several years 
later, on the occasion of a traumatism or any other cause. 

A delayed form of hereditary tuberculosis, more or less analogous 
to hereditary syphilis, is often shown by the presence of osseous or 
articular manifestations. This idea is supported by experiments which 



PATHOLOGY OP THE FCETUS— HEREDITY 215 

prove that apparently sound foetal organs may contain bacilli, and 
also by the researches of Maffucci, who, after introducing various 
microbes into hens' eggs, saw infection occur long after hatching. 

The transmissibility of the bacillus is an undeniable fact. Con- 
genital tuberculosis exists, but it is of exceptional occurrence. More 
frequently the tendency is transmitted : the child comes into the world 
with a vicious nutrition, which manifests itself in lymphatism, scrof- 
ula, or chlorosis, as the case may be, and creates a marked predisposi- 
tion to tubercular infection. 

Congenital Malformations. — Not infrequently infections become 
the starting point of congenital malformations. For instance, in car- 
diac infection the right heart, which is more active, is preferably 
affected. The microbes locate themselves upon the pulmonary valves, 
causing adhesions and consequent stricture of the orifice. The blood, 
unable to pass freely along its normal channel, makes its way through 
the temporary openings and prevents their closure. According to the 
period at which the lesion of the pulmonary artery has taken place, 
there result a permanency of the opening in the interventricular septum 
or of the foramen of Botal, persistence of the ductus arteriosus, com- 
pensatory development of the bronchial arteries, etc. 

Most cases of congenital malformations, however, arise from an- 
other mechanism; and they are connected with disturbances of fecun- 
dation, as has been shown by numerous researches, most of them made 
upon the lower animals. 

When a cell is about to divide, the nucleus presents several impor- 
tant modifications. The chromatic filament, constituting its principal 
part, increases in distinctness; it assumes a stellate form, and, finally, 
separates into a certain number of chromatic rods called chromosomes, 
each one shaped like a V. The number of chromosomes is fixed, and 
always the same for every cell of the same species. Let us suppose 
that they are eight in number. They arrange themselves in a circle 
and perpendicularly to the long axis of the cell, the vertex of the V 
toward the centre. In this position they form the equatorial plate. 
Meanwhile a light spot called centrosome has appeared' at the two 
poles of the cell. Yery soon the chromosomes divide longitudinally, 
thus making 16 half chromosomes in the equatorial plate. During 
this time filaments coming from the centrosomes have reached the 
apex of the divided rods, and, in contracting, draw them toward 
the poles. Eight half chromosomes are thus united to each centro- 
some, producing what has been called amphiaster. At this moment 
evolution is completed; the cellular protoplasm divides, while the 
chromosomes return to quiescence, fuse, and again form a chromatic 
filament. 

15 



216 INTRODUCTION TO THE STUDY OF MEDICINE 

Thus the two daughter cells will each have a chromatic filament 
made of 8 rods, just as the mother cell. 

If we now turn our attention to the ovum, we find that the germi- 
nal vesicle, the part corresponding to the nucleus, migrates to the 
periphery of the ovum when it has reached maturity. A division of 
the nucleus then takes place and produces two nuclei, each containing 
8 half chromosomes. One of these nuclei leaves the cell. This is the 
first polar globule. The remaining nucleus, instead of returning to 
quiescence, immediately divides. The chromatic filaments do not have 
time to grow, and, consequently, can not further subdivide. But the 
two nuclei come into existence in another way : The half rods arrange 
themselves in groups of 4 and form two semiamphiasters ; we thus 
have two half nuclei. One of them, the second polar globule, located 
at the peripher}r, leaves the ovum; the other remains and constitutes 
the female pronucleus. 

Thus this cell, primarily containing 8 rods, first undergoes divi- 
sion, producing 16 half chromosomes. Eight of these leave the cell 
with the first polar globule, and 4 of the remaining 8 leave with the 
second polar globule. Four only remain in the ovum. Consequently, 
the ovum represents but half a cell. 

The spermatozoon also represents a half cell. It is born in a cell 
called male ovum, which, instead of dividing into two, splits into two 
twice in succession without interval of rest. Thus a male ovum pro- 
duces 4 spermatozoa, each possessing half of the chromatic rods be- 
longing to a normal cell. 

When fecundation takes place, a spermatozoon penetrates the 
ovum. This spermatozoon consists of a head corresponding to the 
chromosome, an intermediary part answering to the centrosome, and 
a tail, a mere organ of locomotion similar to the vibrating cilia of 
certain cells. As the result of a special attraction, the head and the 
body, making up the male pronucleus, advance toward the female pro- 
nucleus, which has resumed its place at the centre of the ovum. When 
the two elements meet, the chromosomes unite, and from the fusion of 
the two half nuclei a complete nucleus with the required number of 
chromosomes results. As to the centrosomes, they divide into two; 
then, after performing an evolution of 90 degrees (quadrille of Fol), 
they come in contact. As a result of contact two new centrosomes 
composed of a male semicentrosome and a female semicentrosome 
are produced. Thus a complete nucleus is formed, called the yolk 
nucleus. 

This nucleus divides regularly. Every cell of the body is derived 
from it. Each one of these cells acquires the same number of chro- 
matic rods as the initial cell, and each of them also contains an exactly 



PATHOLOGY OF THE FCET US— HEREDITY 217 

equal part of the male and female elements. The process of karyo- 
kinetic division insures the equal distribution of the two substances 
in every cell. 

Under normal conditions, one spermatozoon fertilizes the ovum, 
but under certain abnormal conditions several spermatozoa find their 
way into the egg. From two to ten have been observed in one ovum. 
Beyond this number the egg succumbs. Eecent researches, particu- 
larly those of Fol, have made a successful beginning in the search for 
the cause of these anomalies of fecundation. Several spermatozoa may 
penetrate the ovum when fertilization takes place before perfect matu- 
rity of the egg. Under these conditions the enveloping membrane is 
not yet sufficiently resistant ; it does not close in quickly enough after 
the passage of the male element, and through the opening thus left 
other fecundating cells may enter. The result is the same when ferti- 
lization occurs too late, since the enveloping membrane has then lost 
some of its strength. Moreover, hyperfecundation takes place when the 
egg comes from a weakened, sickly animal, or, as Fol has shown in his 
experiments on sea urchins, when it is anaesthetized by a current of car- 
bonic acid. 

If two spermatozoa penetrate the ovum in consequence of one of the 
causes just stated, segmentation of the germinal vesicle gives birth to 
four amphiasters, and, consequently, to two cells, which separate and 
become the centre of two embryos. It was formerly believed that this 
double fecundation was due to the existence of two nuclei in the same 
ovum; we now know that it is due to double fertilization of a single 
nucleus. 

The two primitive lines found in cases of double fecundation de- 
velop parallel to each other; from this a twin pregnancy results. The 
two beings have one and the same origin; they represent one being 
divided into two. It follows from this genesis that they are always 
of the same sex, and that a striking physical and moral likeness is to 
be expected. They may have the same thought at the same moment ; 
a sentence begun by one of them may be completed by the other. These 
cases must not be confounded with the twin births resulting from the 
intra-uterine fecundation of two ovules which produces two different 
beings of the same or of a different sex. This must be looked upon as 
the reappearance in man of a phenomenon which is of normal occur- 
rence in most animals. 

When two foetuses develop in the same ovule it may happen that 
the two primitive lines meet and fuse at a specific instant, thus occa- 
sioning the formation of a double monster. The several varieties 
observed under these circumstances may easily be brought back to a 
few types. 



218 INTRODUCTION TO THE STUDY OF MEDICINE 

Let us suppose that the two primitive lines are in a straight line. 
If they meet, the two beings unite at the vertex, the rest of the two 
bodies remaining independent. 

If they form an obtuse or a right angle, the heads and the upper 
parts of the trunk fuse and produce a monstrosity. The best known 
of this class is called Janiceps — i. e., a monster with a double face. 
The fusion having taken place when the head was open in front, the 
two beings have united along their anterior portions, so that each face 
is formed out of an equal part of each being. 

When the two primitive lines meet at an acute angle, the trunk, the 
neck, and the lower part of the head unite. 

Finally, if the lines are parallel, the fusion involves the trunk, 
and if they are slightly divergent, the lower extremities alone are 
joined. 

We have thus far supposed that the two beings developed equally, 
and that the monstrosity resulted from a simple accidental fusion. 
But it may happen that one of the embryos does not develop well ; a 
part necessary to life — the circulatory or the nervous system — may be 
missing, or the subject may remain in a quite rudimentary state. 
Unable to live of itself, it will ingraft itself upon its fellow and 
become a parasite, or it may penetrate into the abdominal cavity and 
thus become a sort of tumour. 

Aside from the facts just considered, monstrosities have been 
known to occur even with normal fecundation. The determination of 
these monstrosities has been brought into evidence by important re- 
searches initiated by Dr. Dareste. The experimenter can at will cause 
the birth of a monster. It suffices here, as everywhere else, to call into 
play external agents — mechanical, physical, chemical, or animate. 

For instance, if the egg, instead of being allowed to remain in its 
normal surroundings, be subjected to the influence of certain motions, 
say rapid vibrations; or if it be kept in abnormal positions — for in- 
stance, in a vertical position ; or if certain cellular groups be destroyed 
during their evolution, as was done by Chabry, a monster will be pro- 
duced. 

If one wants to use physical agents, the egg may be placed in an 
oven too hot or too cold; or, what is a still safer means, its surface 
may be unequally heated. Its growth may be modified even by light 
rays. 

Of late chemical substances have been used. Dr. Fere has pro- 
duced a great number of monstrosities by exposing hens' eggs to the 
influence of volatile poisons, such as ether, chloroform, vapours of 
mercury, or by injecting into the eggs toxic substances, living microbes, 
or soluble products obtained from microbic cultures. 



PATHOLOGY OF THE FCETUS— HEREDITY 219 

Can these researches made upon oviparous animals be applied to 
mammals? This question can now be answered affirmatively. Mon- 
sters are the result of external causes acting either directly on the 
embryo, or, what is more frequently the case, indirectly through dis- 
turbances or lesions of the membranes of the egg. Alterations of the 
amnion, exaggerated or insufficient secretions of the amniotic fluid, 
lesions of the vascular area due to compression, or the trophic dis- 
turbances they provoke, induce irregular evolution of the foetus. The 
best example is that of syphilis, which frequently produces amniotic 
lesions and consecutively causes numerous malformations, such as 
spina bifida, harelip, and clubfoot. 

Every defect of structure and every monstrosity can be explained 
as partial arrest of development or as hypernutrition. 

In the first case certain parts are atrophied, others remain rudi- 
mentary, and unions fail to take place. In the second case certain 
parts develop excessively, or a normally transitory disposition becomes 
a permanent one. If it be remembered that ontogeny is the recapitula- 
tion of phylogeny, it becomes clear that the persistence of a transitory 
disposition represents a variation toward an existing type, or a type 
having existed in another species. Anomaly, then, is the reproduction 
of a state normal in other beings, whether living or extinct. 

Most, but not all, of these anomalies may be transmitted by hered- 
ity. The remark has even been made that the deepest and strangest 
transformations are generally those that hardly ever persist in the 
descendants. As a matter of fact, the malformations we have studied 
— namely, those resulting from a disturbance of the normal evolution 
— must be clearly distinguished from those in a way merely accidental. 
For instance, if the umbilical cord twists itself around one or several 
limbs and causes amputation by pressure, we have an accident which 
will not be transmitted. Similarly, when an infection has produced 
a pulmonary stricture resulting in persistence of the foramen of Botal 
or of the interventricular orifice, the cardiac malformation will not be 
found in the descendants. Accidental lesions, whether congenital or 
acquired, remain isolated; they do not affect the offspring. On the 
contrary, when there are defects in the evolution of the ovum and 
when the anatomical anomaly results from a functional deviation, the 
leading tendency which presides over the development of the being 
and assures the unity of the species seems to be profoundly altered. 
Several generations will be required before the normal type is repro- 
duced. 

We are thus led to ask why accidental anomalies are not trans- 
mitted, while those due to functional disturbances pass to the off- 
spring. This study brings us to the history of heredity. 



220 INTRODUCTION TO THE STUDY OF MEDICINE 

Heredity 

Heredity, says M. Ribot, is the biological law according to which 
living beings tend to repeat themselves in their offspring and to trans- 
mit to them their properties. 

Two great laws seem to govern and explain heredity: the law of 
conservation of the ancestral type and the law of evolution. 

The species possesses a unity, or rather an individuality, and it 
preserves its fundamental characteristics through the ages in such a 
way that men of all times and of all countries resemble each other. 
The likeness, however, is not perfect; certain modifications have oc- 
curred, and it is quite certain that the civilized man of the nineteenth 
century is not identical with primitive man. An evolution has taken 
place. Its significance will be better comprehended if it be remembered 
that the species is ruled by the very laws that govern the individual. 
If we consider a being from birth up to advanced old age, we ob- 
serve in it the working of the two laws just mentioned. It is clear 
that the adult individual is no longer the same as in his childhood, 
and that he will still continue to alter as he advances in years. Never- 
theless, in spite of these continual changes, the individual type has been 
preserved, and in the midst of successive transformations the immu- 
table foundation which maintains the personality of the individual 
remains. 

The species is neither more nor less modifiable. It evolves as well 
as the individual, and also passes through the three phases of growth, 
climax, and decay. The species is preserved through the ages, and it 
maintains through heredity its resemblance to itself, just as person- 
ality preserves that of the individual. 

If we consider inferior beings, heredity seems much more perfect. 
But this is, in reality, an optical defect of our minds, if the expression 
be allowed. It is harder for us to grasp that which constitutes per- 
sonality than to perceive the common traits. Consequently, our atten- 
tion goes to the latter, and thus, because we do not see the differences, 
we believe that all individuals are identical and remain so. In superior 
beings, and particularly in man, we are in the habit of looking for the 
dissimilarities. On closer scrutiny, however, it is easy to convince 
one's self that the resemblances are always preponderant ; the common 
characteristics are more numerous than the points of difference. Con- 
sequently, it can be said that heredity is the rule and nonheredity the 
exception. 

The greatest naturalists and the most celebrated philosophers have 
taken up the study of heredity and have endeavoured to explain it. 
But most of their theories belong to the past. The gemmules of Dar- 



PATHOLOGY OF THE FCETUS— HEREDITY 221 

win and the plastidules of Haeckel are now well forgotten. The 
ideas of Weissmann alone deserve onr attention, although they have 
been vigorously criticised by most authors. 

Weissmann establishes a radical difference between the reproductive 
and the other cells of the body. The former are eternal ; they do not 
die, and thus they assure the perpetuity of the species. This state- 
ment, which may at first seem fantastic, finds support in the study of 
unicellular beings. Amoebae perpetuate themselves by fission. It is not 
exact to say that one animalcule has given birth to another. There is 
neither mother nor daughter, but there are two sisters. Amoebae are 
collateral beings ; and the amoeba of the nineteenth century is the same 
as the one which existed at the beginning of the world. If, perchance, 
a few amoebae die, or the pool in which they live dries up, their death 
is merely a matter of accident. Nothing in the evolution of this pro- 
tozoon doomed it to death. For it natural death does not exist. 

The same reasoning may be applied to the generation of the cells 
of higher animals. The only difference is that they produce two classes 
of cells : cells whose function is to maintain the life of the species, and 
which are consequently immortal, and cells that will constitute the 
body, the soma ; and are therefore destined to die. 

This theory of the continuity of the germinal plasma explains per- 
fectly the preservation of the specific type. But Weissmann pushes his 
theory to its utmost limits and sets up an impassable barrier between 
the somatic and the generating cells. He does not admit that the 
former may have any influence upon the latter, and is led in conse- 
quence to the absolute denial of the transmissibility of acquired char- 
acters. 

At this point we must make a distinction which to us seems to be 
of fundamental importance. Acquired characters may be of two kinds : 
They may be accidental, and therefore not transmissible ; or they may 
be due to functional modifications, and then they are hereditary. This 
distinction leads us to the following new conclusion: Heredity is the 
transmission of functional out not of anatomical modifications. 

Those who deny the transmissibility of acquired characters gener- 
ally cite the Jewish race. For more than three thousand years cir- 
cumcision has been practised among them, and yet the children con- 
tinue to be born with foreskins. In the same way the young of cer- 
tain dogs whose tails and ears have been clipped are born with these 
appendages developed just the same. 

On the other hand, let us consider a functional disturbance. Noth- 
ing is so instructive in this respect as the famous experiment of Brown- 
Sequard. If the sciatic nerve of a guinea pig be cut, the animal be- 
comes epileptic. If it be mated and brings forth young, these will 



222 INTRODUCTION TO THE STUDY OF MEDICINE 

also become epileptic. What is it, then, that has been transmitted in 
this case? Is it the mutilation? Not at all. The sciatic nerve in 
the offspring is quite normal. It is the functional disturbance alone 
which has been fixed by heredity. 

As the development of an organ is regulated by exercise of that 
organ, it is conceivable that transmitted functional modifications may 
be accompanied by anatomical alterations as a consequence. Suppose, 
for example, a man to be gifted by heredity with a superior intelli- 
gence; he will come into the world with particular aptitudes which 
will call forth an unusual development of his cerebral cells. In other 
words, it is not because the brain is highly developed that the intelli- 
gence of the individual is remarkable; but the anatomical centres 
which serve as the substratum of the function have attained an unusual 
development because he has inherited a superior cerebral power. 

Our conception is also applicable to congenital malformations. 
Those resulting from accident — for instance, amputation by the um- 
bilical cord — are analogous to acquired traumatic lesions. They are 
not transmitted. Those produced by functional disorder, and those 
representing an arrest or an excess of development, or a return to some 
ancestral form, are transmitted to a certain number of generations. 

The ideas just expressed are nothing more than the application of 
the great law that the function precedes the organ, and explains, 
directs, and regulates its development. Functional changes alone are 
powerful enough to modify the conservative role of heredity. 

To sum up, we admit that the germ plasm goes through the ages 
without manifesting any tendency to modification. It preserves the 
individuality of the species. The somatic cells, on the contrary, un- 
dergo the influence of evolution. They are affected by external agents, 
and, reacting in their turn on the germinal cells, give them a new 
direction. They tend to modify the primitive type. After the preced- 
ing considerations, again taking up the two great laws already offered 
as accounting for evolution, we can say: The law of conservation of 
the ancestral type finds its explanation in the persistence of the germ 
plasm; the law of evolution finds its explanation in the modification 
of the somatic cells. Accidental changes are not transmissible, be- 
cause they reach the soma only. Functional disturbances are hered- 
itary when the somatic modifications they induce react upon the 
germinal cells. If, in this last case, anatomical changes appear, it is 
because the development and the structure of the organs are governed 
by the functions of which they are the material substratum. 

It is, we believe, in this way that heredity can be understood, and 
that a satisfactory basis can be found for the two laws of conservation 
and evolution by which it appears to be governed. 



PATHOLOGY OF THE FCET US— HEREDITY 223 

Bole of the Two Generators. — In superior beings heredity is de- 
pendent upon two factors. Theoretically, according to the date of 
embryogeny, each cell of the newborn animal contains the same quan- 
tity of male and female chromatine. Accordingly, it would seem that 
the two generators must influence the product in an equal degree. As 
a matter of fact, the results are not so simple. Neither the physical 
nor the moral resemblance is an average. One of the parents exerts 
a preponderant influence. Several hypotheses have been advanced to 
explain this result. 

Orchansky claims that the parent nearest maturity imparts its sex 
and its likeness to the offspring. It is easy to raise objections to this 
theory. It is, however, sufficient to remark that in twin pregnancy 
children are frequently of a different sex. This fact might readily be 
explained if the opinion entertained by breeders be accepted. Accord- 
ing to this view, fecundation gives a male or a female according as 
it occurs at the beginning or end of the catamenia. If the twins are 
not of the same sex, it is because two eggs have been fertilized at two 
different times. 

Among the disorders which, without doubt, must be attributed to 
the collaboration of the two parents, those due to consanguinity de- 
serve attention. It is a matter of common knowledge that marriages 
between relatives give bad results. Such unions are often sterile or 
the children suffer from malformations, polydactylism, albinism, pig- 
mentary retinitis, and especially from deaf-mutism. But this is not 
always the case, and in many instances children bom of such mar- 
riages have been perfectly normal. 

As a matter of fact, the effects of consanguineous marriages are to 
be explained simply as the summation of common characters. As they 
belong to the same family, the chances are great that the parents pos- 
sess the same characteristics and the same physical or moral defects. 
They may be slight in each one of them, but they add themselves and 
increase in the descendants, as they are not corrected by different de- 
fects or qualities. We conclude, then, that marriage between relatives 
will give good results when the pair do not possess analogous defects. 
Otherwise, the least defect may be considerably exaggerated in the 
offspring. Consanguinity must be looked upon as cumulative con- 
verging heredity. 

The same remarks apply to marriages formed between individuals 
of the same social class, and consequently having the same aptitudes, 
tastes, and tendencies. It is a social consanguinity, which may be com- 
pared to family consanguinity. The results are evidently analogous. 
Heredity fixes and exaggerates various defects, but natural selection 
sooner or later interferes. It counterbalances the retrogressive effects 



224 INTRODUCTION TO THE STUDY OF MEDICINE 

of social selection, and ends in the sterility of these degenerate fam- 
ilies. 

The influence of the father is not alone felt by the ovum he has 
impregnated. Individuals born later have been known to resemble the 
first generator in some particulars. Impregnation of the mother, as 
the phrase has it, has taken place. All breeders know that a bitch 
fecundated for the first time by a dog of a different race gives birth in 
the two successive litters to young resembling the first father, although 
the second impregnation was by a dog of the same race as the mother. 

Cases are also cited of women of the white race who, after having 
had a child by a negro, have subsequently, and as the result of inter- 
course with a man of their own race, given birth to children on the 
bodies of which a few black pigmentary spots could be seen. Lingard 
knew a man belonging to a family in which for several generations 
all the males were hypospadic. This man married and had three 
hypospadic children. After his death his wife remarried and had four 
children, all of whom were hypospadic, although her second husband 
was perfectly formed. These four children had in their turn eleven 
children, only one of whom suffered from hypospadia. The structural 
defect transmitted as a result of the maternal impregnation had, it 
appears, modified her organism less deeply, since it showed a strong 
tendency to disappear. 

These facts have such a mysterious aspect that certain authors, 
unable to understand them, have found it easier to deny their reality. 
Those who have tried to explain them have advanced three theories: 
One of them supposes that an imperfect fecundation of a few ova still 
in the ovary takes place at the time of the first fertilization. An- 
other admits a perfect fecundation, and, moreover, supposes that the 
ovum waited for conditions more favourable to its development. 
These two hypotheses are evidently not based upon any known fact. 
It seems more rational to admit an impregnation of the mother by 
the foetus. The latter has inherited the qualities of the father; its 
cells have received from the father a nutritional and functional direc- 
tion manifested by a particular humoral state. As a consequence of 
the continuous changes taking place through the placenta, certain sol- 
uble products reach the mother and impart to her various functional 
aptitudes resembling those of the father. After all, this theory does 
no more than extend to the several forms of impregnation the results 
derived from the study of syphilis. 

All acquired characters, fixed in this way by heredity, pass from 
generation to generation indefinitely, until a time arrives when a 
character long since modified, or even lost, reappears without ascer- 
tainable causes. 



PATHOLOGY OF THE FCETUS— HEREDITY 225 

This is what is called atavism. Darwin has collected a large num- 
ber of examples establishing that certain characters may skip several 
generations. We shall again refer to these facts, which have often 
been put forward in an exaggerated form to explain certain nervous 
variations. 

Heredity of Nutritive Disorders. — Among the functions whose 
modifications may influence heredity, the one most general must first 
be mentioned: nutrition. We shall be brief on this subject, as it has 
already been considered under diathesis. We have seen what part was 
to be ascribed to hereditary modifications in the development of 
arthritis and of scrofula, and we have shown how a slight taint in the 
parents grows worse in the descendants. The fact is striking in 
arthritic persons, and it easily admits of an explanation. When 
arthritism develops under the influence of external causes, the latter 
influence adult cells, which are endowed with a well-defined mode of 
activity. The modification, therefore, is to affect conditions of many 
years' standing, whereas disturbances transmitted by heredity affect 
young cells not yet possessed of a nutritive direction, and therefore 
readily influenced by the impressions they receive. In this way we 
adapt to the history of heredity the conditions which are the very 
basis of children's education. In both cases young cells yield easily to 
influences which they would resist in their adult state. 

In considering a family of arthritics, we find in certain of its 
members clinical tendencies which may coexist or alternate. Among 
its most habitual manifestations, arthritism includes gout, eczema, 
nervous affections — from neuralgias and hemicrania to hypochondria 
and neurasthenia — fat diabetes, gravel, biliary lithiasis, etc. These 
various disorders may coexist in the same individual, but more fre- 
quently they alternate either in himself or in his descendants. For 
instance, a gouty father may have an asthmatic child. In other cases, 
an arthritic's son, suffering in his youth from hemicrania, becomes 
asthmatic when about fifteen; around thirty or forty he is afflicted 
with gout, and later on dies of cerebral hemorrhage. Heredity is 
termed similar when the child suffers from exactly the same dis- 
orders as the father — when they, for instance, are both asthmatic 
or gouty. It is called homologous when the manifestations are 
different. 

Arthritism is the inheritance of civilized people and of the upper 
classes. Most individuals gifted with a superior intelligence are 
tainted by it. Geniuses are often sad, fantastic, one-sided; their cere- 
bral aptitudes have developed unequally; they suffer from deficiencies 
and disorders which at times border upon insanity. In such subjects 
heredity may continue to emphasize the superior qualities. Much too 



226 INTRODUCTION TO THE STUDY OF MEDICINE 

often it assures the predominance of the cerebral disorders and ends in 
mental degeneration or insanity. We shall return to these questions 
when treating of nervous heredity. 

The second diathesis, scrofula, is found, we have said, in children 
born of parents in bad health, suffering from some chronic intoxica- 
tion or infection: alcoholism, syphilis, and especially tuberculosis. 
They are weaklings with flaccid muscles, long and silky eyelashes, 
hypertrophied tonsils, and wide nose. During their first years they 
suffer from impetigo and spurious inflammations entailing voluminous 
adenopathies. In their youth they are in danger of falling a prey to 
osseous or articular tuberculosis, which soon generalizes and prema- 
turely ends their lives. In this way the races of degenerates disappear 
according to the great laws of natural selection. 

The disorders of nutrition determined by chronic intoxications fre- 
quently manifest their influence in the offspring. Children of dipso- 
maniacs are badly developed and present numerous stigmata. Their 
size is below the average. The statistics published by the recruiting 
stations show for each department an almost perfect parallelism be- 
tween the diminution of the size of the recruits and the quantity of 
alcohol absorbed. The evolutive disorder may go so far that young 
men eighteen or twenty years old may be no more developed than 
children of fourteen or fifteen. The pilous system is rudimentary and 
the sexual organs are small. In addition to this infantilism better 
marked malformations may exist, such as cranial or facial asymmetry, 
porencephalia, hydrocephalia, and neurogliar sclerosis of the nervous 
centres. 

If we pass from the anatomical study to that of the functions, we 
shall note numerous disturbances of the nervous system. Anaes- 
thetic and hypersesthetic spots are observed, as well as exaggerated 
reflexes. Sleep may be disturbed by nightmares, terrors, and frequently 
by urinary incontinence. 

The disposition of the subject is sad, morose, and sensibility is 
exaggerated. Intelligence is often precocious, and may seem to an- 
nounce great intellectual qualities. But soon an arrest takes place, or, 
at least, a lack of equilibrium, weakness of attention and of will, and 
some oddities of ideas and behaviour will be noticeable. At times, 
however, a few aptitudes persist, particularly artistic talents. But 
even in this case the asthenia of the nervous system expresses itself 
in a deficient moral sense and in bad and irresistible impulses. 
Among these vicious impulses dipsomania takes a distinct place. It 
is frequently said that an abuse of liquors leads to alcoholism ; but it 
is generally the reverse which is true. The first excess is only the 
occasion which sets in motion a predisposed nervous system. 



PATHOLOGY OF THE FCETUS— HEREDITY 227 

We must hasten to add that heredity is not inevitable. When the 
son of an alcoholic is preserved from the influence of occasional 
causes, the development of dipsomania is retarded or even definitely 
prevented. Unfortunately, the occasions are often almost unavoidable 
for the young man in the workshop, in the army, and, above all, in the 
colonies. Nothing will henceforth stop the person who, following his 
parents, has begun to drink. 

What we have just said of dipsomania also applies to misde- 
meanours, thefts, or crimes. Of late, moralists have justly insisted 
upon the increase of child criminality. If antecedents are looked for, 
it is found that most young criminals are sons of degenerates, and 
particularly of alcoholics. On the slightest provocation the nervous 
system reveals these innate aptitudes. 

Several other less serious disturbances have the same pathogenesis. 
Convulsions, which are too readily looked upon by parents as common 
reactions, take place chiefly in tainted children on account of a para- 
site, an intestinal worm, or an infection like pneumonia. In certain 
instances the disorder may become more serious. The infection may 
localize itself in the predisposed nervous system, particularly in the 
spinal cord, and provoke an infantile paralysis. In other cases an 
intercurrent cause may determine the appearance of a neurosis, of 
hysteria, and especially of epilepsy. In 80 out of 100 cases epileptics 
are born of parents tainted with alcoholism. 

The other chronic intoxications are equally apt to give rise to mor- 
bid disturbances in the descendants. First of all, saturnism may be 
cited. When the mother is poisoned, abortion is the result most fre- 
quently observed. When it is the father, accidents are not less fre- 
quent, as is shown by the following figures, taken from C. Paul: Out 
of a total of 141 cases, there were 82 abortions, 4 premature births, 
and 5 stillborn children. Of the 50 children born alive, 20 died in the 
course of a year, 15 died between the first and the third year, and 14 
were still living. When they survive, such children suffer from various 
morbid manifestations already referred to: frequent convulsions on 
the slightest cause, various degenerations, and serious nervous disor- 
ders, such as epileps}', imbecility, idiocy, etc. 

We need not insist upon the other intoxications. Concerning car- 
bonic oxide, mercury, and morphine, we could repeat what we have 
said about alcohol and lead; but, of whatever nature the intoxication 
be, when degeneration reaches a certain degree, sterility supervenes. 
Thus inferior and defective races disappear. 

Heredity in Infectious Diseases. — The study of intoxications 
leads us quite naturally to that of infections, since it is through their 
toxic products that the microbes act. 



228 INTRODUCTION TO THE STUDY OF MEDICINE 

We have already sketched the history of intrauterine infections; 
we have shown how microbes pass from the mother to the foetus 
through the placenta and how, less frequently, the infection is com- 
municated by the father. 

In the cases where the pathogenic agent does not traverse the pla- 
centa, the product may present a series of accidents called para-infec- 
tious, studied particularly in syphilis. It may be, first, a special 
cachexia, sometimes causing the death of the foetus. Hence, the fre- 
quency of abortions. If it comes into the world at all, the child is 
weak and has a bad constitution. It develops slowly, teething is re- 
tarded and defective; at times the number of teeth is below the nor- 
mal, at other times it is higher; a supernumerary tooth introduces 
itself between the two superior incisors. The teeth are dwarfed, stri- 
ated, eroded ; the superior median incisors frequently suffer a particular 
deformation described by Hutchinson — namely, a notched depression 
in the cutting margin of the teeth. 

The bones are poor in lime salts; hence their deformations, which 
are especially noticeable in the frontal bones and the tibiae. Parrot 
even maintained that syphilis is the great cause of rickets. It may 
well be that it predisposes to digestive disturbances, upon which the 
development of this morbid state apparently depends. 

Other parts of the organism are also affected : keratitis and deaf- 
ness frequently exist. With the dental alterations they constitute the 
triad of Hutchinson. The bodily and intellectual development is slow, 
infantilism is frequent, the genitals remain rudimentary, puberty is 
retarded, intelligence is weak, sometimes nil, and convulsions are fre- 
quent. At times matters go even further. Besides the various stig- 
mata just named, congenital malformations may be observed, such as 
spina bifida, harelip, hydrocephalus, or microcephalus. 

It is chiefly maternal heredity which engenders the disturbances 
just indicated. Paternal influence shows itself preferably in abortion. 
Out of 103 cases of pregnancy due to male syphilitics, only 19 children 
survived; 43 of them died in early infancy, and 41 died in utero or 
were aborted. 

But we may take comfort in the fact that the pernicious effect of 
syphilis slowly decreases and ultimately disappears. It is generally 
admitted that after a treatment of two years there are already some 
chances of having healthy children. After three years, it is almost 
the rule. 

Children of tubercular parents do not fare much better than those 
of syphilitics. They particularly present thoracic malformations, as 
if the respiratory disorders of the parents reacted upon the develop- 
ment of their lungs. Their respiratory capacity is below the average, 



PATHOLOGY OF THE F(ET US— HEREDITY 229 

and their lungs are often affected with emphysema — an alteration 
which Virchow has long considered as congenital. It is probably on 
account of this pulmonary dystrophia that the thoracic cavity develops 
badly. The chest is narrow, lacking in depth, the shoulder blades 
project, and the respiratory muscles are small. 

Finally, in these, as in all children born of diseased parents, the 
following additional stigmata may be observed : Slow teething, insuffi- 
cient ossification, infantilism, defective development of the genital 
organs, of the circulatory apparatus, and particularly of the aorta. 
In the opinion of some authors, this last defect explains the frequency 
of chlorosis. Hanot has insisted on the lobulation of the liver and of 
the kidneys. 

When the parental infections do not go so far as to cause stig- 
mata or bodily lesions, they frequently impart particular nutritive 
habits to the cells of the child and give to their humours a particular 
composition. It is in this way that predispositions and familiar im- 
munities are produced. 

If we leave aside tuberculosis, which we have already considered, 
we may mention a large number of infections of remarkably frequent 
occurrence in certain families. Such is the case in diphtheria, and 
especially in erysipelas, which in 13 out of 100 cases is a family dis- 
ease. The child probably receives from one of its parents a particular 
mode of nutrition, rendering its organism favourable to the culture 
of a special microbe. Consequently these cases must not be regarded 
as similar to those in which one of the parents is diseased and pro- 
duces a child incapable of offering resistance to the first microbe it 
chances to meet. In the former case, the predisposition' is specific ; in 
the latter, it is general. 

Conversely, heredity explains certain immunities. It is justly said 
that infections work havoc when they reach a population for the 
first time. Such was the case with measles in the Faroe and Fiji 
Islands. If these diseases are innocent in Europe, it is because our 
ancestors who had them have transmitted to us a part of the immu- 
nity they acquired. But these facts have slowly been evolved through 
long ages. It is relatively difficult to understand their mechanism. 
Let us rather consider what takes place when immunity has just been 
acquired by the parents. 

The first question is : What is the respective role of the two gen- 
erators? Let us begin with the simplest case: The mother suffers 
during gestation from an infectious disease. We may admit that the 
protective substances formed in her system traverse the placenta and 
confer a certain degree of passive immunity upon the product. Thus, 
a child born of a mother who has had smallpox during pregnancy has 



230 INTRODUCTION TO THE STUDY OF MEDICINE 

acquired immunity from this disease. If a woman be vaccinated just 
before the end of gestation the child will for a certain length of time 
resist the smallpox virus; but this immunity is feebly marked and 
does not last; moreover, it is not a constant result. Analogous facts 
observed upon animals inoculated for rot, symptomatic anthrax, or 
hydrophobia complete the proof of the existence of ovular inoculation 
(Toussaint), but they also demonstrate that the immunity thus ac- 
quired is not well marked and is of short duration. 

The second problem is more interesting. It can be formulated as 
follows : Is it possible for the generators to transmit the immunity 
acquired by them against an infectious disease? 

Ehrlich, who was the first to study this question experimentally, 
inoculated a certain number of animals against tetanus, abrine, or 
ricine. On mating these animals with noninoculated ones, he discov- 
ered that the inoculated females always transmitted a certain degree 
of immunity to their offspring, while the influence of the male was nil. 
Wernicke's researches on diphtheria have confirmed this conclusion. 

Nevertheless, Tizzoni and Centanni and Charrin and G-ley hold 
that immunity may have a paternal origin, although, according to 
them, this is rarely the case. Vaillard, who again took up the ques- 
tion, making use of animals vaccinated for tetanus, cholera, and an- 
thrax, reached the same conclusions as Ehrlich — namely, the father 
exerts no influence, but the mother transmits a slight immunity, which 
may be increased by suckling. 

Three theories have been offered to explain these facts : One of 
them is advanced by Duclaux and supported by Arloing, Charrin, and 
Gley. It is the cellular theory, the only acceptable one if it be ad- 
mitted that the father may transmit immunity. It supposes that 
under the influence of the disease the cells receive a new orientation, 
which persists in the descendants. 

If, following Ehrlich, Wernicke, and Vaillard, the paternal influ- 
ence be rejected, we are quite naturally led to admit that immunity in 
the child depends upon the passage through the placenta of protective 
substances produced in the maternal organism. The immunity of the 
foetus is of shorter duration than that of the mother, because it is a 
passive immunity, a simple impregnation. 

The theory of Vaillard is related to the preceding: The foetus is 
supposed to receive the soluble products, but, instead of simply soak- 
ing the cells, they act as a stimulant upon the phagocytes. This is to 
extend to the problems of heredity the theories of Metchnikoff con- 
cerning the mechanism of immunity. 

In conclusion, our study of heredity in cases of infection shows 
that six eventualities are possible: 



PATHOLOGY OF THE FOETUS— HEREDITY 231 

1. The microbe, coming from the mother, traverses the placenta 
and causes in the foetus a disease at times more serious than in the 
mother (pneumonia, typhoid fever, sometimes syphilis) ; at times sim- 
ilar (smallpox), but in some cases presenting special localizations 
(syphilis); at times different (typhoid fever, anthrax). The mani- 
festations are generally immediate, but they may be tardy (syphilis, 
perhaps tuberculosis). 

2. The microbe comes from the father and invades the organism 
of the foetus, the mother remaining intact ; but she may acquire immu- 
nity against the infection afflicting the offspring (syphilis). 

3. The microbe does not reach the foetus; but the child surfers 
from dystrophic disorders manifesting themselves in malformations, 
stigmata, degenerations, and infantilism. 

4. The child seems normal, but it has received from its mother (or 
from its father?) an immunity, generally not well marked and of 
short duration. 

5. The child receives from its father, or from its mother, a particu- 
lar nutrition, which predisposes it to certain infections. 

6. The child is in no wise influenced by the infection of its parents. 
Thus every contingency may become a reality, from an infection 

leading to speedy death to the total absence of impregnation. 

The very important history of the heredity of neoplasms, and of 
cancer in particular, might find place in the study of chronic infec- 
tions. The question will be dealt with in the chapter devoted to 
tumours. 

Nervous Heredity. — We have several times had to bring in the 
influence of nervous heredity. We have seen in connection with intox- 
ications and infections that disorders caused by external agents could 
be transmitted to successive generations and manifest themselves in 
degenerations, disturbances, or lesions affecting chiefly the nervous sys- 
tem. Chronic alcoholism, saturnism, mercurialism, morphinism, and, 
among the infections, syphilis and tuberculosis, exercise a pernicious 
influence, which we have already considered. An acute intoxication 
may at times produce the same disturbances. For example, drunken- 
ness at the moment of conception is often a cause of degeneration. 
To it belongs a large share in the etiology of epilepsy. 

Moral impressions often exercise a marked effect upon the nervous 
system of children. When conception or gestation takes place under 
the depressing influence of mourning, of annoyances, or during the 
great emotions aroused by public calamities, the children are almost 
inevitably condemned to nervous degeneration. A striking illustra- 
tion is supplied by the case of the young men born during the siege of 

Paris or the Commune. 
16 



232 INTRODUCTION TO THE STUDY OF MEDICINE 

The age of the parents may also have a similar effect. In this 
regard both old age and immaturity exert an influence equally per- 
nicious. If the parents are too young, the first children will be degen- 
erates ; those coming later on and conceived during full maturity will 
be normal. Then, as the years go by, the parents grow weak and 
bring forth children much inferior to their older brothers. It is con- 
ceivable that, under such circumstances, the children of the same 
family do not necessarily resemble each other, especially if we remem- 
ber that most of the causes of dejection, sorrows, terrors, as well as 
diseases, exert only a passing influence. They affect one of the chil- 
dren, not all. Although it is theoretically easy to perceive the influ- 
ence due to these various causes, in practice it is a much harder task. 
It is, therefore, no wonder if the ineluctable law determining heredity 
frequently escapes notice. 

We must also remember that the nervous manifestations grow 
worse in the descendants, and that, after a few generations, they 
become serious enough to entail sterility. This has very justly been 
called progressive morbid heredity. 

The inherited nervous manifestations are not always identical with 
those of the parents, not even always analogous. Three cases present 
themselves: At times there is perfect similarity. This is what fre- 
quently happens as regards hysteria. At times the manifestations 
are only homologous; the disturbances differ in their expression, but 
they are all disturbances of the nervous system. In other cases the 
symptoms seem quite different and their affiliation can not be under- 
stood except by taking into account the idea of diathesis. For in- 
stance, the case may be one of an arthritic whose parents, being gouty 
or diabetic, have had neuropathic children. These transformations 
are not too much to be wondered at. Long ago clinical experience 
taught us that nervous disorders are frequent in all arthritics. In 
this connection we may mention hypochondria, the insanity of gout, 
diabetic pseudo-tabes, and the insanity of rheumatism. It is one of 
these accessory and, in a way, superadded disorders in the parents 
which becomes predominant in the next generation. 

In order that the nervous manifestations to which heredity pre- 
disposes may come to light, an occasional cause must intervene. This 
is, by the way, a notion of capital importance from a prophylactic 
standpoint. The disturbances become apparent on the occasion of a 
traumatism, an infection, an excess, or a moral shock. It is the first 
drinking bout which is the starting point of dipsomania, and it is a 
common infection which, as it causes convulsions or delirium, reveals 
the congenital neuropathy. It may happen that these manifestations 
begin earlier in the children than in the parents. A father whose 



PATHOLOGY OF THE FCETUS— HEREDITY 233 

neuropathic aptitudes do not reveal themselves until late in life may 
have a child who, from his first months, has convulsions. In this 
case hereditary influence would be manifested only at a later date, and 
if the father dies too early — i. e., before having brought to light the 
taints which slumbered in his organism — the problem remains un- 
solved and the child's disorders will seem to be spontaneous. 

Although the parents generally communicate to their descendants 
a mere aptitude, they may at times transmit to them a true disease, 
connected, it seems, with an evolutive disorder. It is a kind of ovular 
affection. As an illustration, we may mention the hereditary ataxia of 
Friedreich, the cerebellar hereditary ataxia of Marie, the progressive 
myopathy of Landouzy-Dejerine, the disease of Thomsen, the so- 
called hereditary trembling. These various diseases have in common 
the following traits : They appear at the same age in the parents and 
in the children; they occur without any occasional cause, and they 
reproduce themselves with uniform aspects. 

In most cases heredity transmits a certain tendency to nervous 
manifestations, and to ordinary reactions which occur on the occa- 
sion of a traumatism, an insolation, an infection, or an intoxication. 
Pneumonia, which in children is so often accompanied by cerebral 
disturbances that an eclamptic and a meningeal form have justly been 
described, so acts, however, only upon predisposed children. It may 
be stated that, even in cases where nervous manifestations seem in- 
evitable, their frequency, intensity, and other characters are governed 
by predisposition. Drunkenness, for instance, is not necessarily ac- 
companied by cerebral accidents. There are men who can absorb great 
quantities of liquor: their reason remains unaffected; and they suffer 
from digestive disorders. Others, on the contrary, prepared by their 
heredity, become delirious at the slightest departure from their ordi- 
nary regimen. 

What we have said in reference to alcoholic poisoning may be 
repeated concerning endogenous intoxications. In uraemia, for in- 
stance, the manifestations vary so much that three clinical forms of it 
have been described according as the accidents involve the digestive 
apparatus, the respiratory apparatus, or the nervous system. It is 
generally admitted that the variability of the symptoms depends upon 
the multiplicity of the poisons, and that the manifestations differ ac- 
cording to the substance which accumulates. We accept this concep- 
tion, but it seems to us that the role of hereditary dispositions must 
be taken into account : The localizations are determined by the state 
of the organs. Uraemia is only an occasional cause that brings to 
light morbid dispositions which until then had remained latent. 

In a certain number of cases the nervous taint explains the devel- 



234 INTRODUCTION TO THE STUDY OF MEDICINE 

opment of the disorders which appear during or after a disease and 
persist for a very long time. This is the case with chorea, hysteria, 
epilepsy, and paralysis agitans. Chorea, for instance, occurs fre- 
quently after an attack of rheumatism, but only when the subject is 
hereditarily predisposed to neuropathia. The same is true of the other 
neuroses. The expressions traumatic hysteria, infectious hysteria, used 
quite frequently, point to this double tendency. It is not that hys- 
teria differs in its symptoms, for they are always the same; but it is 
brought about by a number of occasional causes, all of which act on 
predisposed subjects. 

It would be easy to add analogous considerations with regard to 
all infections which become localized in the nervous system, whether 
it be meningeal tuberculosis, cerebral rheumatism, infantile paral- 
ysis, locotomor ataxia, or general paralysis. In the last two cases 
the role of syphilis, the influence of which is undeniable, must be 
supplemented by the effect of hereditary predisposition, which alone 
explains the localization. 

It is not only in pathology, but also in psychology and sociology, 
that nervous heredity offers an interesting subject of study. Intel- 
lectual aptitudes are transmitted for several generations. There are 
on record families of scientists, of writers, of musicians, and of paint- 
ers. Oftentimes a quality is exaggerated, and, becoming predominant, 
explains the appearance of superior individuals. The power of atten- 
tion, the persistence of ideas, when intensified in the descendants, may 
culminate in a genius. It is also by an insensible increase of the 
familiar qualities that the aptitude for cerebral work develops in civ- 
ilized races, and mental overtaxation becomes possible. 

It is quite certain that it is not every one who can indulge in 
mental overwork. In order to do this one must have been prepared 
by heredity. 

Eeciprocally, a slight disorder may deviate and grow. The tendency 
to fixed ideas may breed melancholia. Cerebral activity may be 
excessive and excite in the child the most varied neuroses. As defects 
increase with age, it frequently happens that children are the more 
degenerate the later they have been conceived. Here is an observation 
which, in this connection, is highly instructive. 

A woman in whom the neurotic tendency was at first little marked, 
but had grown with age, had an attack of influenza when fifty-four 
years old. The nervous symptoms at that time assumed a more serious 
character; she imagined that her soul left her body and sat down by 
her side. This woman had married an intelligent and well-balanced 
man, and had four children. The eldest is thirty years of age ; she is 
a woman of a superior intelligence, but marked as a degenerate by two 



PATHOLOGY OF THE FGETUS— HEREDITY 235 

physical stigmata : facial asymmetry and strabismus. Although now 
married for eight years, she has no children. Her brother, twenty-six 
years old, has a bright but childish intelligence ; he busies himself with 
table tipping and spirit communications. The third one, nineteen 
years of age, is a somnambulist. The fourth, sixteen years old, is a 
hypochondriac with morbid impulses; he several times tried to com- 
mit suicide, and one day attempted striking one of his brothers with 
a knife. 

In this family the accidents have gone on increasing as the mother 
has grown older. The last of her children is in a condition bordering 
upon insanity. 

The statement that insanity is often hereditary is a commonplace 
truth. According to the statistics of Hutchinson, it is hereditary in 
the proportion of 22.6 per cent. 

Consequently here, as everywhere else, heredity is not inevitable. It 
is more frequent when the mother is insane, and it decreases in fre- 
quency as the cerebral disorders become manifest in the parents after 
the birth of the children. 

Aside from similar heredity, the influence of the conditions in 
which the parents are found must be taken into account. Chronic 
alcoholism and drunkenness at the time of conception play the same 
part as the other defects of the nervous system. To these factors 
must be added two others : Overwork on the one hand, and arthritism 
on the other, contribute their part and account for the growth of the 
number of insane persons in the civilized races. The increasing com- 
plications of life, exacerbation of discomfitures and disappointments, 
overtaxation of mental powers, and predominance of the nervous sys- 
tem, sufficiently explain the progress of mental disorders. 

Thus endowed with an hereditary predisposition, the individual 
waits for an occasional cause and then succumbs to insanity. The 
breaking down may happen at the great periods of growth. There is 
an insanity of puberty and, in women, an insanity of the menopause. 
Or the occasion may be childbirth, an external influence, a nervous 
shock, a violent moral impression, an intoxication, or infection. It 
must be said, however, that the interpretation of the disorder is not 
always easy. Alcoholic or venereal excesses and overwork are very 
frequently not the cause of the mental disease, but represent only the 
first symptoms. This is unquestionably the case in general paralysis, 
in which the initial manifestations have often been mistaken for the 
starting point of the disease. 

If heredity is frequent in insanity, it is certainly not inevitable. 
In certain forms, as in chronic delirium, it is constantly found ; while 
it is quite rare in general paralysis. It has even been noticed that 



236 INTRODUCTION TO THE STUDY OF MEDICINE 

the sons of general paralytics are frequently endowed with a high 
order of intelligence and sometimes with genius. 

Genius, Insanity, and Crime. — In a book which created a sensa- 
tion, Moreau de Tours denned genius as a form of neurosis. Although 
this view can not be accepted, it must, at any rate, be admitted that 
cases of genius and insanity and of genius and neurosis are frequently 
found in the same family. It is also well established that a large 
number of highly gifted men present stigmata which, according to the 
happy appellation of M. Magnan, make of them superior degenerates. 
To speak but of the dead, it suffices to mention Socrates talking to 
his spirit, Pascal terrified by hallucinations, and J. J. Eousseau, a 
hypochondriac with secret vices (Confessions). The study of the 
psychic status of superior persons reveals an exaggerated or perverted 
sensibility, the absence of practical sense, queer superstitions and acci- 
dents bordering upon pathology, manias or phobias. This fact is 
becoming a matter of common observation, and has suggested the in- 
teresting researches of M. Toulouse on the mental state and the signs 
of degeneration of our most illustrious contemporaries. 

Keciprocally, an insane person can have sparks of genius. The 
beginning of general paralysis affords abundant illustrations of this 
peculiarity. Tradition understood the relation existing between these 
two extremes and joined them in the term " poetical delirium." How 
many superior men, artists, musicians, and scientists, are looked upon 
as " cracked " by their neighbours ! How many men called lunatics 
by their contemporaries hold the rank of geniuses in the eye of pos- 
terity ! This is because geniuses and lunatics differ from the sensible 
man in the same particular. Their ideas are opposed to those of the 
majority. It is this that makes the great difference between a talented 
man and a genius : the former continues and completes the ideas cur- 
rent about him; the latter departs from them and conceives different 
thoughts. It is no easy matter to determine when an idea springs 
from genius and when from insanity. It may even happen that they 
are analogous in both cases. Specialization in predisposed persons 
depends upon external circumstances. 

It has sometimes been said that relations exist between genius, 
insanity, and crime. In this form the statement is unacceptable. 
There are affinities between genius and insanity on the one hand, and 
insanity and crime on the other; but there are none between criminal- 
ity and genius. Men of genius are superior degenerates, criminals are 
inferior degenerates. For the sake of greater clearness, let us sup- 
pose an angle whose sides extend to an infinite distance : at the apex 
we place insanity, on the ascending side genius, and on the descend- 
ing side crime. Despite the point possessed in common by both 



PATHOLOGY OF THE FCETUS— HEREDITY 237 

psychic states, they evidently diverge more and more from each other; 
their differences increase as the man of genius ascends and as the 
criminal sinks. 

The relationship "between insanity and crime is so evident that 
the question of responsibility rises constantly. Many delinquents who 
formerly would unquestionably have been punished are to-day con- 
fined in asylums. The differentiation is, it hardly need be said, very 
difficult to make, and the idea of partial responsibility, so often ap- 
plied, serves only to indicate the existence of numerous transitions 
connecting insanity and crime. The differentiation can be made from 
two points of view. The public considers any crime as the work of a 
lunatic, and, as a rule, any act the motive of which can not be under- 
stood. The physician must judge differently; he must determine the 
bodily condition of the accused, seek for stigmata, reconstruct his past, 
discover his personal, and especially his hereditary, antecedents. 

In studying the families of criminals, we sometimes find direct 
heredity (25 per cent of youthful criminals are born of criminal 
parents), and sometimes indirect heredity — that is, neuroses, degen- 
erations, mental derangements, and alcoholism. As a rule, child 
criminals belong to families of alcoholics. 

If we turn from the family to the individual, we frequently observe 
stigmata of degeneration. The criminal is liable to irrational fits of 
anger, to night terrors; and at times the disorders are more severe. 
The frequency of insanity in workhouses and prisons is to be explained 
not by the peculiar circumstances under which the prisoner lives, but 
by his hereditary predispositions. Finally, in certain cases, the im- 
pulsive nature of the crime is tardily brought into evidence by the 
occurrence of an epileptic fit, which makes it possible to properly deter- 
mine the moral responsibility of the subject. 

Heredity is no more inevitable here than elsewhere; occasional 
causes, as is always the case, play a very important part. If the indi- 
vidual, predisposed by heredity, is brought up among honest people, 
his chances of not straying from the straight path are good. How 
many people have remained virtuous for the want of an occasional 
cause ! Consider from this point of view the influence exercised by the 
great social perturbations. Eeread, in Thucydides, the story of the 
Athenian plague or review the history of the more recent great revo- 
lutions ; it is always the same picture ; always the same licentiousness, 
hatred, violence, and murder. It is a particular state, perhaps a return 
to an ancestral condition, at any rate, a retrogressive movement, which 
is produced when the fear of punishment grows weak and when social 
hypocrisy is done away with. Contagion propagates the disorder, but 
it reaches those only who carry within them a latent predisposition. 



238 INTRODUCTION TO THE STUDY OF MEDICINE 

If, on the other hand, criminality, as well as insanity, increases 
with civilization, it is because the growing complexity of life breeds 
overtaxation, and requires a new stimulation which seems to be 
favoured by the use of alcoholic beverages. Heredity expresses itself 
under these circumstances in an inability for sustained effort, which 
is the great cause of criminality. 

The facts above stated in a summary way appear conclusive when 
viewed in their entirety. A close relationship must be admitted to 
exist between crime and insanity. These two conditions are separated 
only by our social prejudices. 

Let us hasten to add that the conclusions to which we are led by an 
impartial consideration of the facts in no way affect the right of 
repression; they do no more than change the aspect of the question. 
The right of punishment must be looked upon as a right of defence. 

Physical Stigmata of Degeneration. — Can criminal hereditary pre- 
dispositions be recognised by means of particular bodily characteristics ? 
According to the theory of Lombroso, who answers this question in the 
affirmative, the born criminal presents various stigmata which bring 
him nearer to primitive man. The stigmata are less frequently ob- 
served in man than in woman, although she commits fewer crimes. 
Lombroso meets this objection by the statement that in woman pros- 
titution is the equivalent of crime; as a matter of fact, associations 
of criminals and of prostitutes are of frequent occurrence. Equally 
abnormal, these people come together just as other degenerates do. 
For it seems well established that the various stigmata enumerated by 
the Italian school do not characterize the tendency to criminality, but 
simply the degeneration of the race ; they are found in degenerates of 
all kinds. 

The stigmata of degeneration are extremely numerous. We shall 
limit ourselves to the mention of a few of them: Deformation of the 
cranium and of the face, their asymmetry, existence of abnormal 
sutures, protrusion of the superior or of the inferior maxillary, deep- 
ening of the palate, irregularities in the development of the teeth and 
their speedy decay, harelip, hollow thorax, absence of one or of two 
pectorals, short fingers, lumbar hypertrichosis, exaggerated develop- 
ment of the pilous system in woman and the reverse in man, imper- 
fect development of the genitals, delayed descent of the testicles, bi- 
partite or imperforate vagina. As regards the organs of sense, stra- 
bismus, pigmentary choroiditis, daltonism, deformities of the iris, 
deaf-mutism, anomalous development of the ears, adhesion of the 
lobe, absence of the marginal fold, and anomalies of the helix, which 
in some cases joins the antihelix; among the nervous disorders, stam- 
mering, tics, etc. 



PATHOLOGY OF THE FCETUS— HEREDITY 239 

If we consider the intellectual development, we find all imaginable 
types. At the foot of the ladder, idiocy ; the cerebral functions are so 
reduced that we may consider the subject as a mere medullary being. 
Nevertheless, one faculty may persist: idiots have been known who 
were excellent musicians or astonishing calculators. A little higher 
we find imbecility, and still higher mental debility. Above these we 
find very intelligent, even superior, persons, but they are in some way 
defective; they are odd, eccentric, gifted at times with a partial supe- 
riority, but their character betrays asthenia: defect of judgment, 
inability to look after themselves in life. There are men of genius 
whose mental degeneration is expressed by the absence of practical 
common sense, or by some little defect which astonishes, or by some 
fantastic mania, or incomprehensible phobia. 

Every degenerate, whether superior or inferior, whether bordering 
upon genius, insanity, or crime, very frequently shows an invincible 
tendency to suicide. At times this is the only stigma, or at least 
the most apparent one. They sometimes use childish means, but gen- 
erally they repeat the attempt with increasing earnestness, and gener- 
ally succeed in destroying their lives. 

This tendency to suicide may be transmitted, and, curiously 
enough, each member of the same family uses the same means and at 
the same age. Hammond relates the case of a man who, at thirty-five, 
killed himself in a bath by cutting his throat with a razor. He had 
two sons who committed suicide at the same age and in the same way. 
One of them had a daughter who killed herself at thirty-four, and her 
son put an end to his life when thirty-one years of age. 

The considerations we have presented concerning nervous heredity 
directly suggest practical applications. Prophylaxis may prevent the 
development of the manifestations to which the child is predisposed. 
As above stated, an occasion is required to determine the occurrence 
of the accidents. Consequently, the child should be removed from his 
family; and this becomes an imperative duty when the parents are 
alcoholics. We have shown that the first intoxication is the starting 
point of dipsomania. It is here that the temperance societies are use- 
ful. We must remember that coercion in any form — punishment, in- 
timidation, or repression — never succeed. The effective treatment is 
to place the child in the country in the family of honest and quiet 
people. Moral guidance saves a large number of predisposed sub- 
jects, and even a few delinquents. We do not speak of the hardened 
cases; they are incorrigible. 

It is in this manner that effects of heredity may be successfully 
antagonized, effects which — we can not repeat it too often — do not rest 
upon the race as an unavoidable fatality. 



240 INTRODUCTION TO THE STUDY OF MEDICINE 

It is not impossible for a man to escape from his inheritance; it is 
even possible for him to differ entirely from his ancestors or col- 
laterals. There are cases which appear to defy all our laws and the- 
ories. Occasionally a genius, a lunatic, or a criminal appears alto- 
gether unexpectedly; nothing of his character precedes or follows 
him. No doubt the anomaly is only an apparent one, but its causa- 
tion escapes detection. Perhaps we have failed to take notice of a 
particular influence that has been in action. It is perhaps a return 
to an ancestral type, as in the curious case reported by Darwin in 
which a pigeon of a peculiar colour appears suddenly in a race appar- 
ently fixed by long selection. 

'Conclusion. — The study of heredity completes the history of eti- 
ology. If the causes of diseases must always be looked for outside 
of the organism, the modes of its reactions are governed by predispo- 
sition, aptitude, and resistance transmitted by the parents. The func- 
tional modifications accidentally brought about are communicated to 
the offspring and are often exaggerated in successive generations. Ac- 
cording as the attendant circumstances are favourable or detrimental, 
the family, the race, or the species will show a corresponding improve- 
ment or deterioration. 

By an abuse of expression, it is often asserted that the affections 
of the organs — the heart, the liver, the kidneys, and the nervous sys- 
tem — are hereditary. What is transmitted in most cases is a func- 
tional disturbance — i. e., a simple disposition, which becomes appar- 
ent only under the influence of exciting causes. 

Children born of parents suffering from cardiac, hepatic, or pul- 
monary disorders or from Bright 7 s disease are more likely than others 
to develop lesions of the heart, liver, lungs, or kidneys. But an occa- 
sion will be required in order to make actual the inherited tendency ; a 
new influence, an intoxication, an infection, or an anomalous nervous 
reaction will have to interfere in order that the organ be affected. It 
is in this way that the heredity of visceropathies must be understood. 
It is even probable that what in many cases appears to be hereditary 
pulmonary tuberculosis is due rather to the fact that the offspring 
of tubercular subjects suffer from insufficient respiratory activity, their 
breathing capacity being below the normal. 

Heredity must not be mistaken for "innateness." The latter ex- 
pression designates those cases in which the child comes to life pre- 
senting certain morbid aptitudes, the point of departure of which is 
to be found in some accidental causes having exerted their influence 
directly or indirectly during conception or gestation. 

Innateness is the conclusion of foetal pathology, while heredity is a 
chapter of the pathology of the species. Innateness results from ex- 



PATHOLOGY OF THE FCETUS— HEREDITY 241 

ternal causes which have acted upon the foetus through the enveloping 
membranes. More frequently it arises from toxic or infectious agents 
transmitted through the placenta. At times it proceeds simply from 
bodily or psychic disorders in the parents. A well-constituted person 
generating a child during convalescence from an intercurrent disease, a 
woman under depressing influences during pregnancy, would produce 
an offspring with a particular innateness. It might exhibit nutritive 
disorders or stigmata of degeneration; it would be predisposed to 
neuropathies and easily contract infections. The morbid influence 
having acted upon cells that are young, and, so to speak, malleable, 
would leave an indelible imprint. The disorder would be permanent 
in the child, even though temporary in the parents. 

Innateness frequently results from causes so slight that they escape 
notice. If the great laws of heredity at times seem to fail, it is 
because we do not always perceive the circumstances modifying their 
action. 

In cases of organic as well as of nervous affections, it is a predis- 
position which is transmitted in the majority of instances. Hence, 
the importance of prophylaxis and education. 

Hereditary taints are only too often aggravated by education. The 
sons of neuropathic or alcoholic parents are incited by the examples 
they see in their families to deeds which seal their doom. If, instead, 
they were placed from early youth under the care of persons able to 
start them in a good direction, the effects of heredity would be re- 
sisted, and even completely overcome. 

Unfortunately, it is but seldom that education is used for this 
purpose. Moreover, its influence may be insufficient. If that be the 
case, the disorders of the parents will go on increasing. It is in this 
manner that pathological families are created. If to this be added 
the fact that the same defects are frequent in the same classes, it is 
easy to see how marriages between persons having the same aptitudes 
will still more tend to magnify the hereditary disorders. On the other 
hand, social selection frequently brings about the survival of the weak 
and degenerate. It then seems to supplant natural selection, but it 
does so only temporarily. Infecundity or increasing debility brings 
about the extinction of degenerates. We are thus brought back to the 
great laws regulating the whole evolution, and we are led to look upon 
social selection as a mere chapter of natural selection, sociology being 
simply a chapter of biology. 

As it transmits and fixes certain characteristics, heredity explains 
the evolution of races, their diverse aspects at different epochs and in 
various countries, and by this very reason accounts for their patho- 
logical variations. Diseases are not the same all over the globe ; they 



242 INTRODUCTION TO THE STUDY OF MEDICINE 

differ also according to the period. The variations of pathology in 
time and in space find their explanation in the incessant changes oc- 
curring in the cosmic agents, in the animate beings, and notably in the 
human species. This is the reason why the diseases we observe differ 
from those observed by our fathers, just as they differ from those 
which will come to the notice of our descendants. 

We can now clearly understand the variability of clinical types. 
The various localizations taking place during infections and intoxica- 
tions, the diverse nervous reactions happening on the occasion of a 
traumatism, are not the work of chance. They everywhere and always 
proceed from numerous causes which have influenced the subject or his 
generators. 

If the varied circumstances intervening before and after birth could 
be traced out, if precise information regarding heredity and innate- 
ness could be obtained, and if the external causes playing upon the 
foetus could be known, the future of each individual could be foreseen, 
and its physiological, pathological, and moral history written out in 
advance. For it is quite certain that as all the activities of living 
beings are nothing more than reactions provoked by external agents, 
they must all be interrelated just a£ systematically as the other cosmic 
phenomena. Only it is impossible to discern the innumerable inter- 
vening causes. It is for this reason that the freedom of living beings 
has been so long admitted. Our belief in morbid spontaneity, just as 
our belief in free will, is grounded upon no other foundation than an 
incomplete knowledge of the numerous causes acting upon us. 



CHAPTER XIV 

INFLAMMATION 

Definition — Part played by local lesion — Mode of formation of inflammatory foci — 
Active congestion — Diapedesis — Liquid exudation — Modification of the fixed 
cells — Chemical study of serous exudates — Principal inflammatory processes — 
Pseudo-membranous processes — Suppuration — Chemical and histological con- 
stitution of pus — Principal pyogenic agents — Microbic and nonmicrobic suppu- 
rations — Transformation of pus — Symptoms and course of purulent collections 
— Gangrene — Part played by microbes — Importance of accessory causes — Part 
played by circulatory, nervous, and dystrophic disturbances — Principal ana- 
tomical and clinical varieties of gangrene — Infectious nodes — Tubercles — Ana- 
tomical varieties and histogenesis of tubercles — Principal clinical forms of 
human tuberculosis — Tuberculosis of animals — Unity of tuberculosis — Pseudo- 
tubercles : their varieties and importance. 

Definition. — When a pathogenic cause acts npon any point of the 
organism, it occasions two orders of responsive manifestations, some 
local and others general. Local reactions are due to cellular modifica- 
tions induced at the point of application of the cause, and to modifica- 
tions of a reflex order. General reactions are referable to nervous 
influences or to the absorption of toxines. 

Let us consider, for example, a mechanical agent which has pro- 
duced a cut : The edges of the wound are slightly separated, and the 
open vessels are bleeding. The first reactions will arrest the hemor- 
rhage; on the one hand, the calibre of the vessels will contract in 
consequence of the direct excitation of the nonstriated muscular fibres 
entering into the structure of their walls, and on the other hand as 
the result of a reflex constriction. The blood, flowing with less force, 
will coagulate; fibrine will be formed, and its effect will be to occlude 
the vessel, to assure hemostasis, and to unite the edges of the wound, 
and then serve as nutrition and as a guide to cells which will insure 
reparation. The second act then begins. The cellular elements lining 
the solution of continuity begin to proliferate and form a cicatrix. At 
the same time leucocytes enter the field, some to take part in the for- 
mation of tissues, others to carry away the dead cells and to clear up 
the ground. 

243 



244 INTRODUCTION TO THE STUDY OF MEDICINE 

When a toxic substance is deposited upon the skin, two results are 
possible : In some cases the poison is absorbed without giving rise 
to any local irritation; in others, a reactionary lesion is produced at 
the point of its introduction. The poison has destroyed the cells, and 
these cause a vaso-dilatation, a serous exudation, and oedema by reflex 
action. Thus formed, the local lesion dilutes the toxine, prevents its 
absorption, and in this way protects the organism. 

Let us now suppose that the process is due to a microbe — for exam- 
ple, a pus coccus. When it finds itself in favourable conditions, it de- 
velops. If it only acted mechanically, it might multiply and produce 
a voluminous colony without exciting any general reaction. But, at 
the same time that it multiplies, it engenders toxines which cause 
the death of cells with which they come in contact. Thus is produced 
a necrobiotic zone, which is later surrounded by a proliferative zone. 
Around the cells that have been killed the elements develop in such a 
manner as to circumscribe the infection, to struggle against the 
microbe, and to replace the destroyed parts. Coincidently with the 
occurrence of these first phenomena, the nervous terminations are 
aroused by the microbic toxines and by the dead cells. Their excita- 
tion gives rise to a series of reflex acts which, ending in the active 
dilatation of the vessels at the invaded point, are followed by migra- 
tion of leucocytes and the formation of a serous exudate. In this 
way a local lesion is produced. 

In order that these various phenomena may be produced, the 
microbe must possess a virulence of medium intensity. If it is inof- 
fensive, it can not multiply, and is soon destroyed by the cells. The 
local lesion does not appear, and the infection is aborted. If the 
microbe is too powerful, it secretes a series of substances which pre- 
vent vaso-dilatation, the issue of plasma and leucocytes. The local 
lesion is again absent, but general infection is at once produced. 

The local lesion then represents a fortunate process, and is a bar- 
rier opposed to invasion. Its effect is to circumscribe infection and 
prevent extension and generalization of the process. It may, however, 
have its disadvantages. In certain cases the organism disturbed by the 
arrival of the microbe mobilizes more forces than are required and 
provokes a local lesion liable to become dangerous. Thus, in the 
larynx, under the influence of an infection, as in the case of a burn, 
oedema of the glottis may be produced which will cause death mechan- 
ically. In the lung, active congestion caused by a microbe may bring 
about grave accidents. The animal organism is not capable of pro- 
portioning its intervention to the action of the cause. Hence it is 
that, for a little tubercle situated under the pleura, it will secrete 
three or four pounds of serous liquid. This exudation will hinder the 



INFLAMMATION 245 

development of tuberculosis by the compression it exerts, but its 
abundance will produce accidents, and if timely thoracentesis be not 
resorted to it will in some cases cause death. 

The disproportion between cause and effect is well brought to light 
by a very ingenious experiment of Gamaleia. Two rabbits were taken 
and their cornea slightly cauterized; one of them was kept as a con- 
trol, and soon presented a white spot at the point of traumatism. In 
the other the development of the inflammatory phenomenon was pre- 
vented by injecting into the veins strong salt water. The healing was 
obtained without a cicatrix. It is easy to understand the importance 
of these facts in therapeutics, for we possess the means of stimulating 
or preventing reactions, and notably congestive phenomena. 

Whether there be a local lesion or not, microbes can pass into the 
blood. This liquid, however, is not favourable for them, so they rap- 
idly deposit themselves in the tissues. They develop there, and again 
secrete their toxines, and thus give origin to secondary foci, whose 
mechanism is analogous to that presiding over the formation of the 
primitive focus. 

These two types of foci, primary and secondary, constitute the 
process described under the name inflammation. 

There is no term in medical language that has been more variously 
defined, no process that has been more diversely interpreted. Among 
the numerous conceptions that have been put forth three deserve to 
be mentioned: 

The first, by order of date, is that of Virchow. According to the 
celebrated pathological anatomist, inflammatory phenomena consist 
in degenerations and proliferations bearing on the fixed cells of the 
affected tissues. The vascular changes produced in the morbid foci 
seemed to him secondary. 

Cohnheinr's conception was quite different. The vascular modifica- 
tions were considered by him to be the initial phenomena; the effect 
of vaso-dilatation was to permit the escape of white blood corpuscles 
through the vascular walls, according to a process called diapedesis 
(migration). 

This conception, based on unassailable experiments, gave occasion 
to lively discussion. It was of late completed by Metchnikoff, who 
holds inflammatory reaction to be salutary, as its end is to permit 
the leucocytes to devour and digest the invading microbes — namely, to 
fulfil their phagocytic function. 

Each of these three theories contains a great amount of truth. 

We consider, in fact, that inflammation is "the ensemble of reac- 
tionary phenomena produced at the irritated points by a pathogenic 
agent." In most cases the agent is a microbe, but in some it is a 



246 INTRODUCTION TO THE STUDY OF MEDICINE 

mechanical, a physical, or a chemical agent. Inflammations occa- 
sioned by a foreign body, by insolation, or by the application of 
cantharides are well-known examples. 

Mode of Formation of Inflammatory Lesions. — Inflammation is 
essentially characterized by f our orders of phenomena : vascular dis- 
orders, which may be wanting in the case of a tissue destitute of ves- 
sels, like the cornea; liquid exudations; diapedesis; local cellular 
alterations. 

Congestion and Diapedesis. — The first phenomenon, at least that 
which first attracts the attention of the observer, is represented by re- 
flex vascular manifestations. The cells, irritated by the toxines, excite 
the nervous system, and thus cause an active vaso-dilatation. The 
arterial blood arrives in great quantity, quickly passes through the 
capillaries, and, in consequence of its abundance and rapidity, reaches 
the veins, having nearly preserved its characters. The amount of car- 
bonic acid, although exceeding the normal, is diluted in so great a 
quantity of blood that the liquid remains red in the veins, and, if one 
is bled, it flows in jerks, by reason of the dilated condition of the 
arterioles and capillaries. 

At this moment the patient is sensible of the congestive phenom- 
ena by the heat he experiences, and especially by a sensation of pulsa- 
tion isochronous to the pulse. 

In the second stage the sensation is modified : there is a feeling of 
heaviness, of swelling, and of painful tension. 

In fact, the local condition is changed; the course of the blood 
current has become slower, and there is produced a set of phenomena 
which have been experimentally studied by Cohnheim. In order to 
observe them, one must operate on a frog, draw out an intestinal con- 
volution, and examine the vessels of the mesentery under the micro- 
scope. After a transitory stage of initial constriction, they are seen 
to dilate; then the rapidity of the blood current lessens; the leuco- 
cytes, which were at first carried off by the current, come to adhere to 
the endothelium of the vascular walls. This margination of leuco- 
cytes, to use an expression of Cohnheim, can not occur in the arteries, 
for the too rapid current carries on the few cells which try to fix them- 
selves ; it takes place in the capillaries, and chiefly in the small veins. 
Once fixed, the leucocytes change their form, send out processes, which 
engage between the endothelial cells, separate the -walls of the vessel, 
and thus produce an opening through which they pass out of the circu- 
latory system. This is diapedesis. When the leucocytes have passed 
out of the capillary, the hole that they leave behind them again 
closes up, but not quickly enough to prevent a few red blood corpus- 
cles from passing into the surrounding tissue. 



INFLAMMATION 247 

The leucocytes are not all equally apt to pass out from the vessels 
by diapedesis. It is especially those that belong to the varieties 
known as mononuclear and polynuclear neutrophiles that are en- 
dowed with the most active movements and emigrate most easily. 

The process of diapedesis requires the presence of oxygen, which 
stimulates the activity and motility of leucocytes. It stops if a vein 
is compressed — namely, if an accumulation of carbonic acid is pro- 
duced; conversely, it is accelerated when the flow of arterial blood 
is favoured. Three orders of experiments demonstrate the reality of 
this fact. If the streptococcus or erysipelas be inoculated into the 
ear of two rabbits, and if in one of them the flow of arterial blood be 
accelerated by cutting off the superior cervical ganglion of the great 
sympathetic, it will be seen that exudation is more abundant and 
diapedesis much more intense in the ear deprived of the nerve. On 
drawing a little drop of the exudation there are found in the operated 
animal, at the end of three or four hours, forty times as many leucocytes 
as in the control. This quicker production of oedema and this more 
rapid arrival of leucocytes render the inflammation much more acute 
at the outset, but they precipitate its evolution; the erysipelas is 
healed more quickly and more completely. The results are similar 
when, instead of exciting a streptococcic inflammation, physical or 
chemical agents are resorted to; when, for example, the ears of a 
rabbit are plunged into boiling water, or are rubbed with croton oil. 

Another procedure also brings to light the favourable side of active 
congestion. Filhene inoculated streptococcus in the ear of two rabbits ; 
then, in one of the animals, he surrounded the ear with a small rubber 
bag in which hot water was circulating. The elevation of temperature 
favoured congestion and diapedesis and thus hastened the cure. 

Finally, as was done by Dr. Carnot, acute congestion may be accel- 
erated by vaso-dilating substances, such as amyl nitrite; the result, 
however, is still the same. 

Although congestion favours the exit of leucocytes, it does not 
suffice to explain it; nor is the irritation produced by the air — in 
Cohnheim's experiment a sufficient condition. Eepeating the experi- 
ment, and taking care to place the frog in sterilized air, Zahn ob- 
served vaso-dilatation ; but the phenomena did not go any further. 
Therefore, if diapedesis is produced under other circumstances it is 
because the white blood corpuscles are excited to emigration by the 
numerous bacteria that fall upon the peritoneum from the air. 

What is more curious is the fact that once out of the vessels the 

leucocytes do not travel at random. Urged by a mysterious force, they 

direct themselves toward the place where the microbes are multiplying. 

It is assumed that they are attracted by substances secreted by the 

17 



248 INTRODUCTION TO THE STUDY OF MEDICINE 

bacteria, and by those yielded by the organic cells, which perish in the 
struggle. These various substances exercise an attraction which has 
been called positive chemio taxis. When the microbe is very virulent 
it produces poisons which, unlike the preceding, repel the leucocytes, 
and are said to possess a negative chemiotactic power. 

Serous Exudation. — Coincidently with the emigration of the mor- 
phological elements an exudation of liquids takes place. The exuda- 
tions may be attributed to most diverse causes. Sometimes it is a 
traumatism that determines an often intense oedema in the subcu- 
taneous integuments. More frequently it is physical agents, sunstroke 
or heat stroke, cold or burning, that excite a serous swelling. A good 
many chemical agents act similarly. The action of slight caustics or 
energetic revulsives is well known ; it suffices to mention the blister of 
epispastics. As in all other cases, the most numerous and varied illus- 
trations are found in the group of infections. Abundant serous exu- 
dations are produced at the point where anthrax is inoculated; also 
at the seat of and around diphtheritic lesions and in corresponding 
ganglia. They are also formed under the influence of staphylococcus, 
and especially of streptococcus. Lastly, it is very common to see in 
serous membranes exudations referable to a tubercle situated in the 
neighbourhood. 

From a mechanical standpoint, liquid exudations are often divided 
into two groups, according as they are of inflammatory or chemical 
origin. 

In the latter case some hindrance to the venous circulation is 
admitted. The fact is undeniable: quite tight compression of a limb 
is sufficient to cause a serous exudation in the cellular tissue. But, in 
order to produce this phenomenon, the constriction must be brought 
to bear on all the vessels ; anastomoses are in fact so numerous that 
the constriction of one vein is followed by no effect. If oedema is 
produced in certain cases it is because the influence of another factor is 
added to the mechanical action — for example, a microbic toxine or an 
active congestion. Ligation of the three principal veins of the ear 
in a rabbit, for instance, does not provoke oedema unless a few drops 
of a sterilized culture of a microbe, like Proteus vulgaris, be injected 
at the same time beneath the skin, or unless the superior cervical gan- 
glion of the great sympathetic be severed. In man, a phlebitis, even 
when it affects a vein of little importance, often causes considerable 
oedema. The fact is striking in the case of varicose phlebitis; but 
this is not a mechanical phenomenon, since ligature of the same 
vessel produces absolutely nothing. 

It may be asked, therefore, whether a great number of exudations 
attributed to mechanical influences are not due to more complex pro 1 



INFLAMMATION 



249 



cesses. It may be questioned whether the oedema occurring in cardiac 
and Bright's disease patients is not often favoured by the develop- 
ment of the microbes of the skin, which tend to penetrate into the 
integuments under the influence of malnutrition. The same remark 
applies to the viscera. It is very probable that pulmonary oedema is 
often due to the action of external germs, which tend to develop 
in a lung not sufficiently supplied with blood. The same remarks 
are applicable to serous membranes. The ascites of cirrhotic patients 
is not always to be ascribed merely to a circulatory difficulty; it is 
probable that venous stasis permits the escape of intestinal microbes, 
which irritate the walls of the portal vein or even of the peritoneal 
serous membrane. The hydrothorax of cardiac patients seem still 
more frequently to be referable to bastard pleuro-pulmonary infec- 
tions. In a word, in order that exudations be produced, it is in most 
cases necessary that an additional process be established to complete 
the mechanical action of venous stasis. 

The chemical distinctions which it has been attempted to establish 
between inflammatory and mechanical exudations seem very fragile, 
since there exist numerous transitions between the results obtained. 
It is asserted that inflammatory exudations are denser; the areometer 
shows 1,020 instead of 1,010 to 1,015; they contain more proteid 
matters, more fibrinogen, and they often coagulate spontaneously. 
Mechanical exudations, on the contrary, do not coagulate, for they 
contain little of the cellular elements capable of furnishing the fibrin 
ferment. 

Pleural exudations especially have served for the investigations of 
chemists. Mehu found notable differences, according as the exudation 
was inflammatory or mechanical. Here are some figures, borrowed 
from Halliburton, which give the particulars : 





Pleurisy. 
(Acute inflammation.) 


Hydrothorax. 
(Torpid inflammation.) 




1,020 -1,023 
35 - 52 

0.1- 1 
12 - 30 
11 - 33 

7.3- 9 


1,012 -1,016 

13 - 25 per 1,000 
0.06- 0.1 " 


Proteid matters 






4 - 7 " ' 




7-18 " 


Mineral salts 


7.3 9 " 







These figures show that exudations are never due to simple 
transudation; they would then have a fixed composition. The min- 
eral salts alone seem to escape by exosmosis, since they do not vary. 
The organic matters escape by a process of true secretion; it is a 
question of a vital phenomenon connected with the irritation of endo- 
thelium. 



250 INTRODUCTION TO THE STUDY OF MEDICINE 

But it is also easy to convince one's self that there are not radical 
differences between the two varieties of transudations. Numerous 
figures of transition prove that the process is always complex, and that 
in most cases inflammation is added to mechanical action. 

Modifications of the Fixed Cells. — While the various modifications 
just described are being produced, changes by no means less interest- 
ing occur in the cells of inflamed tissues. The endothelia of the ves- 
sels swell up; the cells of mesodermic origin — namely, the fixed cells 
of connective tissue — the clasmatocytes of Ranvier, and even the cells 
of adipose tissue, return to their embryonal state, recover their round 
form, and recuperate their motility and contractility. 

The proper cells of tissues, the epithelial cells, are more highly 
developed, and hence more fragile. Many of them perish. Some- 
times, as if overwhelmed by the action of toxines, they are from the 
outset struck by death and undergo coagulation necrosis. In other in- 
stances they first become hypertrophied ; their protoplasm becomes 
translucent, then atrophies and undergoes granular, hyaline, colloid, 
vitreous, and fatty degeneration. Those situated around the inflamed 
zone resist better, and their irritation is expressed by karyokinesis and 
proliferation. 

Evolution of Inflammation. — If the inflammatory phenomena are 
not too intense, the round cells, of mesodermic origin, tend toward 
organization; infectious nodules are formed, the most highly devel- 
oped types of which are represented by tubercles and syphiloma. On 
the part of epithelial cells are observed nodular formations, adenoma, 
perhaps also epithelioma. We shall return to this question, which 
touches the much-disputed problem of relationships between inflamma- 
tions and neoplasms. 

If inflammation is intense the cells are killed. According to the 
nature of the agent and the condition of the organism, and according 
to the elements attacked, granulo-fatty degeneration, necrosis, false 
membrane, in which a tendency toward organization still persists, sup- 
puration, and gangrene are observed. 

The clinical manifestations of these various anatomical processes 
are extremely variable. However, in the case of free acute inflamma- 
tion we observe a certain number of interesting disorders. 

These are, first, the four cardinal signs of inflammation — pain, 
heat, redness, and swelling (dolor, color, ruber, tumour) — which occur 
at the invaded point. We shall make a complete study of these in con- 
nection with suppuration. There is produced at the same time an 
increased functional activity having for its centre the affected point. 
On the part of neighbouring glands an increased secretion will be pro- 
duced. But the liquid is often altered and contains only mucus. In 



INFLAMMATION 251 

more intense cases the disturbance is expressed by a reverse phenome- 
non- — namely, a dryness of the parts, in consequence of arrested 
secretion. 

In the cases where evolution is favourable, the elements that have 
perished are eliminated, thrown out, carried away by wandering cells, 
or are destroyed by neighbouring cells. Their disappearance is fol- 
lowed by the development of a tissue that will fill up the empty place. 
This is sclerotic tissue, veritable cicatricial tissue. As in all other 
cases, the effects may exceed the end. The sclerotic tissue may be 
exuberant and form veritable tumours, designated under the name 
keloids; or, obeying its retractile tendency, it will contract, compress 
the neighbouring parts, interfere with their activity, and thus provoke 
new disturbances. 

General Reactions. — The local phenomena of which we have just 
indicated the mechanism are frequently attended by general manifesta- 
tions. Whenever the local inflammation is somewhat intense, numer- 
ous disturbances become manifest. The temperature of the subject 
rises suddenly or slowly, the appetite is lost, the tongue is coated, 
digestive disorders set in, and respiration is accelerated. The patient 
experiences a feeling of malaise and of lassitude; he often complains 
of headache, and becomes incapable of continuing his occupation or of 
fixing his attention. At times matters go still further: quiet or vio- 
lent delirium occurs, the tongue becomes dry, and the lips are fuligi- 
nous. The condition is disquieting, notwithstanding the fact that 
the lesion has remained absolutely local. 

We shall again refer to all these manifestations, which are for the 
most part dependent upon intoxication. The soluble products, pro- 
duced at the morbid focus, thus profoundly modify the organism and 
give rise to general reactions, including fever. These reactions repre- 
sent the most striking example of the relations existing between the 
various parts of the economy under pathological as well as under nor- 
mal conditions. We shall make a special study of this when describing 
the functional synergies and morbid sympathies (Chapter XIX). 

We shall now consider the mode of formation and the meaning of 
the principal inflammatory processes. 

Pseudo-membranous Processes 

Pseudo-membranous processes are usually divided by German au- 
thors into two groups. They describe under the name croupous exu- 
dation that form which is superficial, and under the name diphtheritic 
exudations that form which is more profound — namely, interstitial. 
These expressions are bad; they lead to confusion, and must be aban- 
doned. But they correspond to a just idea, or at least to a necessary 



252 INTRODUCTION TO THE STUDY OF MEDICINE 

distinction. Two varieties of pseudo-membranous processes are to be 
admitted. In some cases it is a question of the formation of a new 
membrane covering up a mucous membrane, of which it reaches the 
most superficial parts only. In others, the pseudo-membranous appear- 
ance results from a necrosis, from a more or less profound diphtheroid 
gangrene. The former process is realized by certain microbes, notably 
by the bacillus of diphtheria; the latter characterizes the destructive 
affections of toxic or microbic origin. Caustics, like nitrate of silver, 
and the most varied microbes may produce lesions of membranous 
appearance. Such is the case in stomatitis, known as ulcero-mem- 
branous stomatitis, which were better called superficial gangrene of the 
mouth; such is also the case in muco-membranous enteritis. In these 
two affections the so-called false membranes are nothing else than parts 
or shreds of the altered mucous membrane. 

There is, then, a capital difference between the two processes. The 
first is dependent upon a general reaction of the organism; the second 
is the work of a pathogenic agent. The former is characterized by the 
development of a concrete exudation at the surface of the mucous 
membrane; the latter by the exfoliation and expulsion of a pre-exist- 
ing necrosed part. 

Leaving aside the history of diphtheroid gangrenes, to which we 
shall hereafter refer, let us consider only the true pseudo-membranous 
process. 

In the habitual conditions of life this process may be considered 
as always dependent upon a microbic infection. However, a specific 
diphtherogenic microbe does not exist. The false membrane repre- 
sents a quite common reaction, which may be called forth by a great 
number of bacteria. It suffices to consider what occurs in the throat. 
Pseudo-membranous sore throats may be produced by numerous 
microbes. Along with Loeffler's diphtheritic bacillus, which holds the 
first place, are to be ranked streptococcus, pneumococcus, pneumo- 
bacillus, tetragenes, etc. 

On the other hand, an agent capable of giving rise to the forma- 
tion of a false membrane may in other cases produce an edematous 
exudation or a purulent focus : witness streptococcus or pneumococcus. 
The latter microbe produces false membranes, exudations very rich 
in fibrine, or true suppurations. The difference depends upon the 
virulence of the microbe, upon the seat of the lesion, and upon the 
condition of the subject. Secondary influences intervene in all cases, 
even in the case of Loeffler's bacillus. The diphtherogenic action of 
this microbe is manifested only on parts in contact with air; subcu- 
taneous inoculations produce only oedema rich in fibrine, but no false 
membranes. 



INFLAMMATION 253 

It is a law well established to-day that the morphological ele- 
ments do not act except by their secretions. This law may be applied 
to the pseudo-membranous processes. It has for a long time been 
believed that false membranes were not produced except under the 
influence of living bacteria acting upon an altered mucous membrane. 
At present it is demonstrated, at least as regards the diphtheritic 
bacillus (the only microbe that has been studied from this point of 
view), that the false membrane is due to the action of toxines. It 
has been possible to reproduce laryngitis, bronchitis, conjunctivitis, 
and vulvitis, all pseudo-membranous, by simply depositing the pure 
toxine of the diphtheria bacillus upon the mucous membrane; but as 
this had already been established with regard to suppurations, the 
more slowly the poison is applied the greater will be the success. 

It is probable that the microbic toxine acts by primarily altering 
the cells with which it comes in contact; but this action is slow. If 
vibratile cells of the trachea are taken and placed in toxine and in 
simple bouillon for comparison, their movements are seen to persist 
in both cases for almost the same length of time. 

The altered cells secondarily provoke a vaso-dilatation, and then 
a diapedesis of leucocytes. Thus far the phenomena have nothing 
special. Subsequently, within twenty-four to forty-eight hours, the 
false membrane develops. 

To explain the production of the latter, several theories have been 
advanced. The simplest idea is to assume an exudation of a fibrino- 
genic substance which coagulates on contact with the air. Wagner sus- 
tains the view that false membranes are produced by the cells of the 
tissue, which unite by means of prolongations. 

To-day the consensus of opinion is that exudation is consti- 
tuted, on the one hand, of fibrinogenic substance, and, on the other, 
of altered cells. The fibrinogenic substance escapes from the vessels, 
and finds itself in the best conditions for coagulating; it is in contact 
with the air, it meets with dead leucocytes, which here, as everywhere 
else, play a great part in coagulation; it is spread out upon a mucous 
membrane whose cells are diseased. Now it is known, from Cohn- 
heim and Weigert, that the epithelial as well as the endothelial cells 
do not oppose coagulation of exudations except when they are intact. 
Finally, a certain role is to be attributed to the cells of tissues, which 
become fibrinified according to the process described by Weigert under 
the name of coagulation necrosis. 

Thus made up at the expense of the fibrine of blood and of the cells, 
false membranes present quite variable aspects. They may be seen in 
serous exudations, where they float in the liquid; elsewhere more 
abundant, they line the two surfaces of the serous membrane and 



254 INTRODUCTION TO THE STUDY OF MEDICINE 

may bring them to adhesion. Finally, they frequently have their seat 
upon the surface of a mucous membrane, to which they adhere more or 
less intimately. 

Should one of these false membranes be stripped off, the ulcerated 
surface becomes exposed, • slightly bleeding; and this proves that we 
are in the presence not of a simple deposit, but of a profounder process. 

The detached false membrane is quite resistant; it does not disin- 
tegrate when agitated in the water, thus being distinguished from 
pultaceous layers or mucous concretions. It is dissolved by lime water 
and by hypochlorite of soda; its richness in fibrine explains why it 
decomposes oxygenated water. 

Examined microscopically, it is found to be composed of anasto- 
mosed fibrinous threads, sending out prolongations which attach them- 
selves to the subendothelial tissues by a series of arcades; this ex- 
plains why the production is adherent. The fibrine appears under the 
form of lamellae, compact masses, or spiral threads. In the midst of 
the fibrine are seen fat, mucine, degenerated cells, and, in most cases, 
numerous microbes. 

Thus constituted, the false membrane may grow by the addition of 
new layers of fibrine and be reproduced when it is stripped off. The 
considerable quantity of fibrine which may thus be eliminated is not 
to be wondered at. Dr. Dastre has shown that this substance is very 
rapidly produced in the organism. If the greater part of the blood of 
a dog be defibrinated and again introduced into the vessels, it will soon 
be found that the blood is as rich in fibrine as normally. 

When a false membrane occupies the surface of a mucous mem- 
brane — that of the throat, for example — a moment will arrive in for- 
tunate cases when the secretions of the subjacent glands will detach 
the pathological productions and bring about their exfoliation; the 
remaining adherent debris will be picked up by the phagocytes. This 
process may be assisted by means of pilocarpine, which, by favouring 
glandular secretion, hastens exfoliation of the false membranes. In 
some cases the latter disappear in consequence of a histochemical 
transformation; they undergo a granular or a hyaline degeneration. 

In other cases, in tissues, and particularly in serous membranes, 
the false membrane, far from disappearing, becomes organized. The 
fixed cells and the wandering cells proliferate, following the false 
membrane, which serves them as a guide. Simultaneously the tissue 
becomes vascularized. In this way adhesions are formed, which may 
subsequently be absorbed, undergo sclerotic transformation, or become 
infiltrated with calcareous salts. 

The production of false membranes is to be considered as a re- 
sponsive process of defence. It is a barrier opposed to the penetration 



INFLAMMATION 255 

of microbes or of toxines. In some eases it is a re-enforcement of tis- 
sues, which prevents their destruction under the influence of patho- 
logical causes. The false membranes developed upon serous mem- 
branes are intended for the same end. 

Eeactions often exceed the end, or, after having been useful, become 
harmful. The diphtheritic false membrane may by its seat produce 
grave and fatal mechanical disturbances. The adhesions of serous 
membranes embarrass the movements of subjacent viscera, cause de- 
formities, compress important organs or excretory passages, and thus 
give rise to a whole series of new morbid manifestations. 

Suppuration 

Suppuration is one of the terminations of inflammation. It is 
characterized by the production of a liquid exudation, containing 
numerous necrosed cells, designated by the name pyocytes or pus cells. 

Characters of Pus. — According to the microscopical aspect, three 
varieties of pus are usually admitted : 

Phlegmonous pus, the laudable pus of the old authors, is a yellow- 
ish-white, creamy, thick, odourless liquid. It is met with in phlegmons 
and in purulent pleurisies. 

Caseous pus is more consistent. It resembles certain soft cheeses; 
hence the name given to it. 

Lastly, thin pus is formed of a serous liquid, floating upon clots 
and frequently containing necrosed or sphacelated elements and fatty 
acids ; it often exhales a disagreeable or fetid odour. 

The colour of pus is no less variable. Usually yellowish, it may 
be of orange, brownish-red, or greenish colour. As to blue pus, the 
expression is bad; there is no suppuration presenting this colour. 
Under this name have been designated cases where dressing materials 
have imbibed a colouring matter — pyocyanine of Fordos — produced 
by a special bacillus {Bacillus pyocyaneus) which is not pyogenic by 
itself. 

No relationship exists between the aspect or the colour of pus. and 
the cause which has determined its development. We shall make an 
exception only of the suppuration of pneumococcic origin, which is 
thick, greenish, and rich in fibrine, often having the aspect of false 
membranes. It is rather owing to the points where it is developed that 
suppuration presents particular characters. In subcutaneous or 
pleural collections the pus is phlegmonous, thick; in the meningeal 
membranes of the brain it is greenish ; in the liver, of chocolate colour ; 
and reddish in the lung. When it is of osseous origin it often con- 
tains fat and small splinters of bone. If it takes origin in the glands 
of the skin it produces a furuncle or a carbuncle — a lesion remark- 



256 INTRODUCTION TO THE STUDY OF MEDICINE 

able for the presence of sphacelated fragments of cellular tissue, which 
constitute the core. 

There may also be found in pus foreign bodies, tissue fragments, 
elastic fibres, animal or vegetable parasites, hydatids, actinomycetes, 
organic liquids, bile, milk, urine, faecal matters, and alimentary frag- 
ments. These various substances are of great importance from a 
semeiological standpoint; they inform us as to the origin of pus and 
as to the possibility of organic fistulas. 

It is generally easy to recognise pus. In case there should be any 
difficulty, for example, in the presence of inspissated mucus or of ste- 
atomatous contents of certain sebaceous cysts, it suffices to make a 
microscopical examination. The same method of exploration is useful 
in determining the presence of pus in certain organic liquids. In the 
urine, for example, it may be recognised by the addition of ammonia, 
which causes a curdled precipitate. In certain cases, to which we shall 
again refer, serous membranes contain chyliform exudations, which are 
formed of an emulsion of fatty matter. It is easy to recognise the 
nature of the latter. The microscope reveals the absence of pus cells, 
and ether completes the demonstration by dissolving the fat. Ether 
may also aid in the recognition of certain collections rich in choles- 
terine ; it dissolves this substance, and, on evaporation, leaves a deposit 
of crystalline lamellae the shining aspect of which is very charac- 
teristic. 

Histology of Pus. — Microscopic examination, which is to be re- 
sorted to in doubtful cases, shows in pus a great number of cells 
known under the generic name pyocytes (pus cells). According to 
their aspect and origin, they are divided into two groups : 

A. Large cells — namely (1) leucocytes, of which three varieties 
are admitted: mononuclear, polynuclear, and eosinophilic leucocytes; 
(2) Gluge's corpuscles, made up of the union in spherical masses of 
fatty granules arising from the destruction of cells; and (3) spheral 
cells derived from connective tissue. 

B. Small cells, including (1) small white globules, called lympho- 
cytes; (2) round cells derived from connective tissue; and (3) perhaps 
free nuclei. 

Chemical Constitution of Pus. — Chemically, pus is a neutral 
liquid, sometimes alkaline, exceptionally acid. Its density varies from 
1,020 to 1,040. Allowed to stand, it does not coagulate, but sepa- 
rates into two la3'ers: a superficial layer, the pus serum, and a pro- 
found layer, containing cells. In general, there are 700 or 800 parts 
of serum to 200 or 300 parts of globules, but these figures are very 
variable. In some instances pus contains only 25 per 1,000 of mor- 
phological elements. 



INFLAMMATION 257 

Pus includes various albuminoid matters — serum, globuline, nucleo- 
albumin, albumose or peptone, fat, lecithine, and, in old foci, choles- 
terine. It also contains glycogen, which is contained in its cells ; pto- 
maines, ferments possessing the property of peptonizing gelatine ; and 
pigments derived probably from the colouring matters of blood and of 
tissues. It contains no urea and no sugar, except perhaps in cases of 
diabetes. 

Mechanism of Suppuration. — The origin of the liquid constituting 
the pus serum is evidently to be traced to the blood serum. That 
exudation depends upon a process of osmosis is inadmissible. In 
fact, in this hypothesis it would invariably have the same chemical 
constitution and contain the same elements as the blood plasma and in 
the same proportions. The differences observed from one case to 
another indicate that we have to deal with a true secretion : the altered 
cells draw certain substances in an elective manner; the vascular 
endothelia, disturbed in their function by the pathogenic cause which 
provokes suppuration, now allow one substance, now another, to pass. 

When the exudation is formed, its composition is subject to modi- 
fication by neighbouring cells or those which enter into it, and by 
pathogenic agents, particularly by the microbes which multiply in it. 
This is why albumoses and peptones are almost constantly present. 
These bodies, which are not found in the blood, have a local origin 
as the result of the action exercised by cells or microbes upon albu- 
minoid matters. At any rate, it is useless to dwell upon these facts, 
as we have already studied an analogous question in presenting the 
general history of inflammatory exudations. 

The cells that are found in pus are derived from two sources. 
The smallest number originate locally; the cells of connective tissue, 
the adipose cells, perhaps even some differentiated cells, are trans- 
formed into round elements. But the majority of purulent cells are of 
hemic origin. These are leucocytes, which, having collected in great 
numbers, escape from the vessels by diapedesis and accumulate at the 
point attacked. Some of these cells remain living; the majority suc- 
cumb in the struggle they sustain against the pathogenic agent — i. e., 
the cause of inflammation. It is precisely this death of the cells that 
characterizes suppuration. Hence the exudation comprises innumer- 
able cellular elements, which, no longer of any use, represent nothing 
more than true foreign bodies, which are to be reabsorbed or elimi- 
nated. It is under these circumstances that the physician frequently 
intervenes, and, by an incision, permits the escape of the purulent 
collection. In many instances such collections are again formed, often 
with extraordinary rapidity: within forty-eight hours a pleuritic 
exudation of one or several litres may be reproduced. Now, if we 



258 INTRODUCTION TO THE STUDY OF MEDICINE 

remember the number of leucocytes present in such an exudation, we 
can not but be astonished at so great a multitude of cells which the 
blood can furnish. 

Under normal circumstances the blood contains 6,000 leucocytes 
to the cubic millimetre, which, for the 5 litres contained in the 
human body, amounts to 30,000,000,000. Pus, having on an average 
125,000 white blood corpuscles to the cubic millimetre, contains 
125,000,000,000 to the litre, and that means that it contains four 
times more than the blood mass. 

We are thus led to ask, Whence come the innumerable leucocytes 
which are found in the exudation? Their presence seems to be ac- 
counted for by a previous leucocytosis. Instead of the normal figure of 
6,000, the blood contains 15,000 to 20,000, and even 36,000 leucocytes 
per cubic millimetre. These leucocytes are produced in the hemato- 
poietic organs — in the spleen, which is often increased in volume; 
in the lymphatic glands, which are swollen ; and, above all, in the mar- 
row of the bones. The osteomedullary tissue, overcharged with fat 
in a state of rest, is modified as soon as the organism is in need of 
leucocytes. The pathogenic agent, which locally determines an in- 
flammation tending to become suppurative, directly or indirectly 
stimulates the vitality of the marrow of bones; the fat is absorbed, 
the cells are multiplied and fill up all the tissue. These modifications, 
so marked under a histological examination, are already appreciable 
to the naked eye: the marrow assumes a red colour, recalling the 
aspect which it presents at birth, where it is very rich in cells. This 
is a return to the foetal condition. 

The microscopic examination of pus, by showing the pathogenic 
agent, also informs as to the cause which has given rise to the pro- 
cess. In the majority of instances the development of suppuration is 
dependent upon the presence of microbes which may be brought to 
light by simple microscopic preparations. In order to obtain precise 
information, however, it is indispensable to have recourse to bacteri- 
ological cultures. 

Pyogenic Agents. — It has thus been recognised that suppuration 
may be caused by very numerous microscopic agents, which we shall 
divide into five groups : 

1. Bacteria habitually Pyogenic. — They are normally encountered 
upon our integuments, and, although they may give rise to very varied 
manifestations, they especially provoke suppuration. These are 
Staphylococcus aureus and alius, streptococcus, pneumococcus, colon 
bacillus, and Micrococcus tetragenes. 

2. Specific Pyogenic Bacteria. — They produce suppurations which, 
from a clinical standpoint, present a particular evolution. Only three 



INFLAMMATION 259 

microbes enter into this group : gonococcus, the bacillus of soft chan- 
cre, and the bacillus of glanders. 

3. Bacteria accidentally Pyogenic. — This group comprises quite 
numerous species, which produce more or less well-differentiated le- 
sions, and may in certain cases cause suppuration. These are, for 
example, the tubercle bacillus, which causes most of the cold abscesses, 
and the typhoid .bacillus, which may also produce pus, notably in 
bones. 

4. Vegetables capable of becoming Pyogenic. — Here it is a question 
of parasites more elevated than bacteria. Such are streptothrix (of 
which Streptothrix bovis or actinomycetes is the most important), as- 
pergillus, and oidium. 

5. Finally, the last group comprises the animal pyogenic parasites 
— namely, the sporozoa capable of inducing suppuration. The most 
important is the amoeba of dysentery, which, it seems, may cause 
abscesses in the liver. 

Of all these pathogenic agents, staphylococci and streptococci are 
most frequently encountered. In bringing together a certain number 
of well-prepared statistics, it is found that, out of 144 cases, staphylo- 
coccus has been discovered 114 times and streptococcus 26. Fre- 
quently, several species are met with united in the same focus : staphy- 
lococcus and streptococcus often coexist; they may further be asso- 
ciated with pneumococcus and with colon bacillus. Such polymicrobic 
foci are generally transitory, for one species gradually attains the 
upper hand, commonly staphylococcus, and the others disappear. 

When a pyogenic species is introduced into an organism suppura- 
tion develops, especially if the bacteria are numerous. We have already 
cited figures given by different authors. W. Cheyne finds that 250,- 
000,000 cocci must be injected in order to produce an abscess. Bujwid 
declares that 1,000,000,000 is insufficient. The differences are ex- 
plained by the variability of virulence. In order that suppuration may 
appear, microbes of a medium activity are required. If too attenuated, 
they are destroyed without having produced any disturbance; if too 
energetic, they at once invade the economy and provoke a general in- 
fection, as septicaemia ; in both cases the local lesion is wanting. The 
effects also vary according to the point where microbes are intro- 
duced. In cartilages suppuration is very rare. What is more curious 
is the fact that tissues whose structure is nearly identical behave very 
differently : abscesses are frequent in the brain but exceptional in the 
spinal cord. Among the muscles, only three are generally affected : 
the deltoid, the sterno-cleido-mastoid, and the iliac psoas. The lung 
does not easily suppurate, at least the healthy lung; but when it is 
already altered, pus cocci develop in it with the greatest facility. The 



260 INTRODUCTION TO THE STUDY OF MEDICINE 

digestive canal is often traversed by the same cocci, which, if the 
mucous membrane is intact, are able to develop and produce no acci- 
dent whatever. 

The most sensitive part of the organism is the anterior chamber 
of the eye; it is 8,600 times less resistant than the subcutaneous cellu- 
lar tissue. As regards the serous membranes, the variations are quite 
considerable : the arachnoid and the pleura easily suppurate ; the 
peritoneum is endowed with a very powerful antimicrobic action. 

The pyogenic agents may be directly introduced into our tissues — 
for example, by an instrument charged with microbes. But in con- 
nection with mechanical agents there is a fact of considerable impor- 
tance on which we have already dwelt. A clean-cut wound, even when 
it is contaminated, often unites by first intention. This is true of 
nearly all wounds, even of operative wounds which appear the most 
perfect. Ideal asepsis, therefore, is an illusion. Numerous pyogenic 
microbes which produce no disturbance are found under the best 
dressings. If, on the contrary, the wound is contused, or the borders 
lacerated, or the tissues mangled, the microbes develop with the great- 
est facility. 

Suppuration is also favoured by the presence of a foreign body. 
For example, the extraction of such a body often suffices to arrest the 
discharge without any other intervention. 

Chemical agents exert upon the tissues an analogous action, which 
therapeutists have turned to account : Thus, Croton oil, when spread 
upon the surface of the integuments, gives rise to the formation of 
pustules. Antiseptic substances, if too concentrated, favour suppura- 
tion. Before killing the microbe they cause death of the cells, and 
consequently diminish the resistance of the organism; they produce 
an effect which is just the reverse of the one expected. 

In cases where suppuration seems to appear spontaneously — name- 
ly, without traumatism or direct inoculation — it is often dependent 
upon a modification in the normal secretions, which, being diminished, 
are no longer capable of sweeping the excretory passages. The bac- 
teria enter them and develop. Their action is often favoured by the 
presence of some foreign body obstructing the canal. Thus, a hepatic 
calculus, by plugging the bile duct, permits the colon bacillus to invade 
the biliary channels and induce a suppurative angiocholitis. Likewise, 
if the cavity of the ileocaecal appendix becomes obstructed, the microbes 
contained in it will be apt to exercise a pyogenic role. This appendi- 
citis may be experimentally produced in the rabbit. Ligation of the 
appendix is sufficient to transform it into a purulent pouch. But if a 
cutaneous fistula be formed at the same time the ligature is applied, 
thus permitting the escape of the liquid produced within the intes- 



INFLAMMATION 261 

tine, no suppuration will appear, no matter how small this opening 
may be. 

In the course of infectious diseases the secretions are often dimin- 
ished or suppressed. In typhoid fever, for example, the mouth is dry. 
Formerly, when no antiseptic precautions were taken, the bacteria of 
the buccal cavity entered Steno's duct and quite often caused paro- 
tiditis. As is known, this event has at present become altogether ex- 
ceptional. 

Finally, the pus cocci manifest a great tendency to invade parts 
already diseased. Lesions of the skin and mucous membranes and 
pulmonary alterations easily become the seat of suppuration. Vari- 
ous poisons probably favour the development of suppuration by alter- 
ing the tissues through which they are eliminated. The pustules of 
acne and the furuncles observed in cases of iodism and bromism may 
be explained in this manner. It is perhaps convenient to admit a 
more complex process. These substances cause digestive disturbances 
ending in an exaggeration of gastrointestinal putrefactions. Now, it 
is demonstrated that substances thus taking their origin may cause 
furunculosis (Bouchard). This form of cutaneous infection is easily 
cured by the administration of certain insoluble antiseptics — benzo- 
naphthol or beta-naphthol ; the fermentations decrease, and the cuta- 
neous glands, no longer having to eliminate an excess of toxines, be- 
come capable of resisting microbic invasion. 

Likewise, diabetes favours suppuration in consequence of humoral 
modifications. Clinics abound in illustrations, and experimental 
pathology furnishes similar results. A number of staphylococci, which 
produce nothing when injected beneath the skin, cause an abscess if 
a cubic centimetre of a 25-per-cent solution of glucose be introduced 
with the microbe. They cause a phlegmon if the sugar is injected 
into the veins. 

Lastly, all causes which weaken the organism favour suppuration. 
It is well known how frequently abscesses occur during convalescence 
from grave diseases. 

The suppurative focus, of which we have just studied the consti- 
tution and mode of development, may remain local or give rise to sec- 
ondary foci. In order for the microbic process to become generalized, 
the pathogenic germs must of necessity invade the circulatory system. 
In certain cases their passage into the blood is preceded by the devel- 
opment of a phlebitis. The microbe alters the walls of a vein, and 
the blood coagulates there. The clot invaded by the pathogenic agents 
subsequently breaks down, and its debris, serving as vehicles for the 
microbes, gives rise to suppurative lesions at different points. In other 
instances the pus cocci reach the blood either by passing through the 



262 INTRODUCTION TO THE STUDY OF MEDICINE 

venous walls without occasioning previous coagulation, or after having 
penetrated the lymphatics and traversed the glands, which have been 
able to retain them for an instant. 

Once in the blood, the microbes do not remain there, as this 
medium is unfavourable for them. They therefore deposit themselves 
in the various tissues. From that moment three results are possible : 
The microbes may be destroyed by phagocytes; they may be at least 
partially eliminated by the sweat and the urine ; or they may multiply 
and produce visceral abscesses according to a procedure identical to 
that which explains the formation of the primary abscess. 

When a focus is developed, whether primary or secondary, sub- 
cutaneous or visceral, the organism tries to react : it forms a barrier 
which tends to circumscribe the infection. In fortunate cases the 
microbes diminish and in the end disappear, so that the focus passes 
through five successive phases : It at first contains living and virulent 
microbes ; then living, but attenuated ones ; then cadavers of microbes 
which are still visible under the microscope, but which can no longer 
be cultivated; at last it no longer contains any bacteria, but it is 
sterile. 

The nonmicrdbic suppurations are frequently observed in old 
lesions, provided there be no communication with the exterior. They 
are often met with in the Fallopian tubes ; in the liver, in which about 
forty observations have been collected; and more rarely in the brain 
and around the kidney. 

Generally well borne, these foci may, however, give rise to various 
accidents, despite the absence of living microbes, notably to paroxysms 
of fever, but once opened up they heal with the greatest facility. 

In view of the fact that purulent collections may in time become 
sterile, we may inquire whether in certain cases pus could not develop 
under the influence of simple chemical substances without the inter- 
vention of any living element whatever. This question, which has 
given rise to most animated controversies, is to-day solved. Numerous 
experiments made in animals and therapeutic inoculations practised in 
man have established that pyogenic properties may be attributed to a 
great number of substances, of which we shall mention metallic mer- 
cury, calomel, silver nitrate, turpentine, Croton oil, antipyrine, solvines, 
sapotoxine, digitoxine, etc. The chances for suppuration to be effected 
will be the greater the larger the quantity of substances injected, the 
more concentrated the solutions used, and the more slowly they are 
introduced. Five drops of turpentine injected at once does not pro- 
duce any pus; the same quantity introduced from a small celluloid 
pouch, from which it should flow slowly, will give rise to its appear- 
ance. The latter experiment, which we owe to Poliakoff, undoubtedly 



INFLAMMATION 263 

explains a great many discordant results. Other contradictions are 
due to the fact that effects vary according to the animal species. Non- 
microbic suppuration is produced in the rabbit with much more diffi- 
culty than in the dog. Thus it is seen that generalization of particu- 
lar cases has, as always, led to error. 

When it is remembered that the microbes themselves act only 
.through the agency of the soluble matters which they produce, it is 
not astonishing that certain chemical compounds should have a pyo- 
genic action. The cultures of Staphylococcus aureus contain an alka- 
loidal substance, Leber's phlogosine, which is probably nothing else 
than a product of the true toxine, an albuminoid matter, isolated by 
Christmas, the injection of which causes suppuration. 

Similar results have been obtained with the cultures of strepto- 
coccus, with the extracts of putrid meats, and with ptomaines like 
cadaverine. Behring has demonstrated that the pyogenic power of 
the soluble products is annihilated by iodoform. Thus is explained the 
action of this drug, which, although feebly antiseptic, exercises such 
a favourable influence upon suppuration. 

Finally, from the important researches of Buchner, it appears 
that the protoplasm of bacteria contains pyogenic substances. It may 
be concluded from this fact that when microbes are destroyed and dis- 
integrated the pyogenic substance contained in them is given off, 
spreads in the focus, and may favour its extension. 

To sum up, suppuration is a common process which may be due 
to a great number of chemical substances and animate agents. Clin- 
ically, pus is almost always produced by microbes. But the latter act 
only through the agency of the soluble products which they secrete or 
through the substances contained in their protoplasm. We must there- 
fore conclude that suppuration is always occasioned by chemical sub- 
stances. 

Evolution of Purulent Foci. — Once formed, the purulent collection 
tends to make its way in the organism. It advances and extends by 
means of the ferments which the pus contains and which digest the tis- 
sues. It thus directs itself toward the exterior or toward a hollow 
organ, preferably following the paths half traced by the aponeurotic 
or muscular interstices, and the vascular or nervous sheaths. Then 
the collection opens and the pus flows out. 

At the same time a work of reparation begins, which in abscesses 
experimentally caused is already appreciable on the second day. Buds 
are formed, which tend to fill up the suppurating cavity; they con- 
tain voluminous cells, destined to free the focus from the cellular 
cadavers that may be found there. The buds that come in contact 
unite and give origin to a soft or hardened cicatrix, which is some- 
18 



264: INTRODUCTION TO THE STUDY OF MEDICINE 

times exuberant. In the latter case it constitutes a sort of tumour 
called keloid. 

In certain cases pus becomes encysted, and may undergo fatty de- 
generation and assume the aspect of chyle. 

Chyliform collections have chiefly been observed in serous mem- 
branes. They have been the subject of numerous discussions. In 
certain cases there has been, it seems, a true collection of chyle, due 
to rupture of an important vessel or even of the thoracic duct. In 
most cases it is a primarily purulent collection whose microbes have 
succumbed, and whose cells, having undergone granulo-fatty degen- 
eration, have completely disintegrated; the freed fat has been emulsi- 
fied and has imparted to the liquid a milky aspect. Such collections 
are mainly observed in the pleura, peritoneum, and tunica vaginalis. 

If the liquid part is absorbed, there remain thick, caseous masses, 
which may become infiltrated with calcareous salts. 

Symptoms. — The development of a purulent focus is expressed by a 
series of symptoms, the principal ones being the four so-called cardinal 
symptoms, namely, pain, heat, redness, and swelling. 

Pain is generally the first phenomenon by date. It is due to an 
increased flow of blood and to active congestion occasioned by the 
introduction of a pyogenic agent. The arrival of arterial blood is 
expressed by a slight hyperesthesia of the skin and by a sensation of 
throbbing synchronous with the pulse. At the end of a certain time 
the pulsatile pain gives place to a sensation of constriction, due to dis- 
tention of the resisting parts and to stretching of the nervous ter- 
minations. Subsequently, when the purulent collection is produced, 
the spontaneous pain disappears, and profound pain is caused only on 
pressure. 

Shortly after the beginning of the painful manifestations, some- 
times at the same time, more rarely before, pain and redness appear. 
These two phenomena are less constant; they are wanting when the 
focus is profound — for example, when it is inclosed in the cavity of a 
bone. Therefore, particularly appreciable in cases of superficial lesions, 
they are related to the increased circulation of blood and to karyo- 
kinesis. However, even in cases of profound suppurations, the tem- 
perature may rise in those regions of the skin which cover the parts 
attacked. Local thermometry reveals a rise of temperature by a few 
tenths of a degree. 

The fourth phenomenon, swelling, is evidently appreciable only 
in cases of foci superficially situated or tending to bulge outward. 
However, even if the collection is profound, one may often observe a 
sometimes considerable oedema in the integuments which cover it. 
The semeiological importance of this phenomenon is very great. In 



INFLAMMATION 265 

cases of pleurisy, for instance, the oedema of the thoracic wall indi- 
cates almost surely the purulent nature of the exudation; similarly, 
in cases of suppurative osteomyelitis, the integuments are frequently 
infiltrated with an abundant serous exudate. 

Besides the four cardinal phenomena above indicated, there are 
functional disturbances to be considered. The glands in the neigh- 
bourhood of the focus may secrete in exaggerated amounts or give 
origin to liquids of an anomalous constitution; in other cases, on the 
contrary, the secretion stops. 

The muscles often lose their power. Stokes has made known the 
paralysis of the diaphragm occasioned by purulent exudations of the 
diaphragmatic pleura. The palate is equally impotent in cases of 
intense phlegmonous angina. Finally, in peritonitis, tympanites is 
likewise explained by a paralysis of the nonstriated muscular fibres 
of the intestine. 

The natural tendency of purulent collections is to make their way 
outward and be evacuated. Once open, the course is toward a cure; 
but a favourable evolution may be hindered by manifold causes. The 
opening may be insufficient; then the pus tends to propagate toward 
other regions and causes channels and cavities; or the fistula will 
now and then close up, with the result that various accidents will occur, 
due to the retention of the pus; or the opening will be made into an 
important organ and be followed by grave or fatal accidents; or, 
finally, the focus will be secondarily invaded by germs, which will 
induce putrid fermentations. 

When the evolution seems to be on the point of terminating, an 
accidental cause may revive the process. Transitory indisposition, in- 
digestion, fatigue, nervous shock, moral impression, sometimes un- 
timely intervention, will determine the spread of the suppuration. 

From the standpoint of their course, abscesses are often divided 
into two groups : hot abscesses and cold abscesses. 

Hot abscesses include circumscribed phlegmon and diffused 
phlegmon. 

Circumscribed phlegmon is a collected, well-defined suppuration, 
generally surrounded by a membrane called pyogenic. Diffused 
phlegmon, badly limited, tends to extend and invade the neighbour- 
ing parts; it is accompanied by grave phenomena, and in some re- 
spects it resembles erysipelas; at any rate, it is streptococcus which 
intervenes in both cases. 

Cold abscesses are at present often considered as tuberculous ab- 
scesses. It is quite certain that tuberculosis is the principal cause 
of the suppurations which are designated as " cold," because they 
arouse no local or general reaction. But the same process may be 



266 INTRODUCTION TO THE STUDY OF MEDICINE 

referable to very numerous agents. The Staphylococcus aureus may 
produce, especially in the skin, chronic abscesses, the evolution of 
which in every way recalls that of a tuberculous focus. These abscesses 
are mainly observed in children: their nature has been demonstrated, 
on the one hand, by cultures which have revealed the presence of the 
staphylococcus, and, on the other hand, by direct inoculation of the 
virulent products into guinea pigs — inoculation that has not been fol- 
lowed by the development of tuberculous lesions. 

Staphylococcus has exceptionally been able to produce analogous 
lesions. The typhoid bacillus especially locates itself in the marrow 
of bones in convalescents from typhoid fever, and causes chronic osteo- 
myelitis, which, without the assistance of bacteriology, one would be 
tempted to consider tubercular. 

There exists a last variety of nontuberculous cold abscesses : these 
are produced by actinomycetes. It has exactly the same course as in 
tuberculosis. Error will be avoided by a careful examination of the 
pus. There will be found in it small yellow grains, which have been 
rightly compared to the flower of sulphur. Examined under the micro- 
scope, these small masses appear to be formed of radiated filaments 
terminating by clublike swellings at their periphery. 

Gangrene 

Definition. — Gangrene is a morbid process essentially characterized 
by the mortification and putrefaction of tissues. 

Mortification does not suffice to define the process. If it exists 
alone, the condition is designated as necrobiosis. In order that gan- 
grene may occur there must be putrefaction in addition to necro- 
biosis. Now there can be no putrefaction without microbes. There- 
fore gangrene is always of microbic origin, while necrobiosis may be 
produced by most varied agents. 

Let us suppose, for example, that the principal artery of one of 
the lower extremities is obliterated and the circulation interrupted: 
gangrene will appear, for the microbes of the integuments will invade 
the parts deprived of circulation. Without the intervention of 
microbes there would be only a simple necrobiosis. In fact, if the 
obliterated artery be that of a part inaccessible to air — one of the cere- 
bral arteries, for example — the tissue will degenerate ; in this particu- 
lar case there will be softening, but, owing to the absence of microbes, 
no gangrene. 

The microbes causing gangrene act upon the altered tissues as they 
would upon the tissues of cadavers. Between gangrene and cadaveric 
putrefaction, however, there are decided differences. First, the affected 
parts are still the seat of certain reactions. There is an influx of 



INFLAMMATION 



267 



serum, lymph, and blood pigment ; the bacteria, attacking the exudate, 
produce new fermentations therein. On the other hand, whatever may 
be the extent of the lesions which give origin to the gangrene, it is 
inadmissible to assume that all the cells are attacked. Some of them 
survive, at least those that are in the peritoneum, and these are able 
to react and thus impart a special character to the process. 

We shall state, therefore, that cadaveric putrefaction is a fermenta- 
tion in dead tissues. Gangrene is a putrefactive fermentation in tis- 
sues altered but not completely deprived of life. 

Efficient and Accessory Causes. — There is no gangrene microbe. A 
great number of bacteria may give rise to this process. 

Pathogenic agents have been divided by some authors into two 
groups : those capable of inducing gangrene in healthy tissues — name- 
ly, the two successive stages of necrobiosis and of putrefaction — and 
those which require the pre-existence of necrobiosis and which are 
simply putrefactive. 

This division, which possesses a certain importance, is not perfect, 
for, even in the case of the most active agents, accessory or predis- 
posing causes play a considerable part. It is altogether exceptional to 
see healthy tissues invaded by gangrene. 

The causes favouring the development of gangrene may be divided 
into two groups, according as they act directly on the tissue to lessen 
its vitality, or indirectly, by means of the vessels, the nervous system, 
or the blood. Each group comprises a certain number of secondary 
causes, which may be classified in the following manner : 

Agents. 



Direct alterations of tis- 
sues by 



Indirect alterations by 



Mechanical. 
Physical. 
Chemical. 
Animate. 

Circulatory 
disturbances. 

Nervous 
disturbances. 



r Vascular compressions and obliterations. 
■I Arteritis. 
I (Edema. 

r Encephalo-myelitic alterations. 
< Neuritis. 
I- Raynaud's disease. 



f Humoral alterations. 



Dystrophic J Auto-intoxications. 



disturbances. 



Exogenous intoxications. 
_ Infections. 



The influence of alterations produced by various traumatic agents 
is evident. Ragged, contused wounds, mechanical compressions and 
lesions of vessels and nerves, and comminuted fractures considerably 
favour the development of all microbes in general, and of those of 
gangrene in particular. 



268 INTRODUCTION TO THE STUDY OF MEDICINE 

Intense heat and cold act in the same way by diminishing the re- 
sistance of the cells and disturbing the circulation. Chemical agents 
are still more important. Caustics, venoms, organic liquids, and bile 
or urine abolish the resistance of the tissues in which they spread. 
Urinary infiltration, consecutive to rupture of the urethra, for exam- 
ple, greatly predisposes to suppuration and gangrene. The interven- 
tion of animate agents which prepare the way for the action of gan- 
grenous agents is much more complex, and seems to be concerned not 
in a local lesion, but in a disturbance of the entire organism. 

At the head of causes acting indirectly we shall first of all cite 
those which disturb the blood circulation, notably those diminishing 
the supply of arterial blood. Whether arteriosclerosis, acute arteritis, 
thrombosis, or embolism be present, gangrene can not appear without 
the intervention of microbes. This is demonstrated by the classical 
experiment of Chauveau on twisting the testicle. This operation en- 
tails a simple atrophy of the testicle; but if before practising it 
microbes be injected into the veins, the organ deprived of its vessels 
will become an easy prey and will be attacked by gangrene. 

The arterial obliteration does not need to be complete. A simple 
stricture suffices, especially when connected with an infectious process. 
The microbes located in the vessel walls secrete substances which com- 
plete the annihilation of the resistance of the surrounding tissues. 
Vascular spasm may have the same effect. In symmetrical gangrene 
of the extremities, or Eaynaud's disease, simply a vaso-constriction is 
produced, followed by small patches of gangrene, which are to be 
attributed to the microbes of the skin. 

Disturbances of the venous system are much less important, be- 
cause either the re-establishment of the circulation is easier or the 
accumulation of dark blood is less harmful to the tissues than the 
absence of arterial blood. (Edemas, for example, even when abundant, 
are rarely invaded by gangrene ; phlebites are almost never followed by 
this accident. 

The influence of the nervous system is evidenced by numerous 
facts; the eschar, which rapidly ensues in hemiplegic or paraplegic 
patients, is explained by the nutritive disorders which permit microbic 
invasion. Lesion of a nerve may have the same effect. Brown-Sequard 
has shown that section of the sciatic nerve in the guinea pig is fol- 
lowed by gangrenous phenomena in the extremities. Here it is a mat- 
ter of secondary infection, which is avoided by protecting the paw 
against the action of the external germs. The inoculation of strepto- 
coccus beneath the skin of the ear of a rabbit no longer produces a 
simple erysipelas, but a gangrenous inflammation, provided the au-' 
riculo-cervical nerve, which furnishes sensibility to the region, be sev- 



INFLAMMATION 269 

ered at the same time. In man, confirmation of these facts is found 
in those cases in which peripheral neurites produce sphacelus and at 
times massive gangrene. 

Finally, modifications in the composition of the blood play a con- 
siderable predisposing part. It suffices to mention the influence of 
diabetes and the frequency of gangrene in this affection. In other 
cases it may be a poison — ergot or mercury, for example — which, by 
modifying the circulation or the vitality of the cells, permits the devel- 
opment of the gangrene germs. 

As to infections, their influence is complex. They act by disturbing 
the circulation, paralyzing the nervous system, causing auto-intoxica- 
tion, altering the various protective organs, diminishing the secre- 
tions, and by disturbing nutrition. Gangrene results from the synergic 
action of these various factors. 

Bacteriology of Gangrene. — The microbes capable of producing 
gangrene are divided into two groups. There are, first, those which 
especially possess this power. The chief representative is a bacillus 
described by Pasteur under the name septic vibrion, also known to 
the school of Lyons as bacillus of gangrenous septicaemia, and by the 
German authors as bacillus of malignant oedema, but better termed 
bacillus of gaseous gangrene (page 111). 

The disturbances caused by this bacillus in man have been vari- 
ously designated as malignant oedema (Pirogoff), acute purulent 
oedema, swift gangrene {gangrene foudroyante, Maisonneuve), invad- 
ing traumatic gangrene (Bottini), and as gangrenous septicaemia 
(Chauveau). These various expressions can not be accepted, since 
they give rise to confusion. The terms gangrenous septicaemia, and 
that of septic vibrion, applied to the microbe, have only served to lead 
to numerous errors. It is therefore better to adopt the expression 
gaseous gangrene, which has the advantage of recalling the nature of 
the phenomena observed. 

As is known, the microbe of gaseous gangrene is an anaerobic ba- 
cillus. It is very widely distributed, and is found abundantly in the 
soil, on vegetables, and in the mud of waters ; it is encountered 
almost constantly in the residue upon porcelain filters. 

Poincare and Mace have found it in alimentary preserves, vegetable 
or animal. 

This ubiquity explains its presence in the bodies of living beings. 
It may be found in the saliva, and it is often met with in the intes- 
tine, especially in the horse. Discharged with the faecal matters, it is 
spread in abundance upon the soil. 

Being anaerobic, the bacillus can not develop on solution of con- 
tinuity exposed to the air; it can only vegetate in ragged ones and in 



270 INTRODUCTION TO THE STUDY OF MEDICINE 

contused tissues. The recent investigations of Penzo and of Besson 
have even established that the spores of this bacillus, freed from tox- 
ine, do not produce any disorder; they do not act except when another 
microbe is injected with them, or when profound lesions are produced 
in the tissue. Thus, that which occurs under natural conditions 
where the gangrenous bacillus is introduced into wounds along with 
foreign bodies, earth, and numerous microbic germs, can be experi- 
mentally produced. 

There exist other microbes that may behave like the bacillus of 
gaseous gangrene, but they have mainly an experimental interest. A 
few of them, however, have been encountered in man, but in an ex- 
ceptional manner. 

The second group which we must study is represented by a series 
of bacteria which are gangrenous only on occasion. These are the 
pyogenic microbes, notably streptococcus, staphylococcus and proteus. 
We have shown that these agents begin by exciting necrosis at the 
point of their introduction. If, however, the organ is vigorous, re- 
action appears and is expressed by suppuration. On the other hand, 
if the organ is weakened, altered, or incapable of sufficient reaction, 
necrosis attains the upper hand and gangrene develops. Keciprocally, 
the bacteria which produce gangrene, like the bacillus of gaseous gan- 
grene, only cause abscesses in resisting animals. There are, then, 
numerous transitions between suppuration and gangrene; the exist- 
ence of gangrenous phlegmons is the clinical proof thereof. The ex- 
perimental proof is furnished by a well-known experiment of Bujwid : 
Staphylococcus, the pyogenic agent par excellence, causes gangrene 
when sugar is conjointly introduced into the organism. 

Localization of Gangrenous Process. — All parts of the body may 
be attacked by gangrene, provided they communicate directly or indi- 
rectly with the exterior. 

The skin is often attacked; the most diverse lesions, such as ery- 
sipelas, impetigo, herpes zoster, the pustules of smallpox and vari- 
cella, at times even simple abrasions, may be followed by gangrenous 
patches. But in order that this eventuality may be realized, a special 
debilitation is required in the subject, whether he be a convalescent 
or suffering with a chronic affection. Thus are developed the eschars 
upon the sacrum, following some minute lesion, in convalescents from 
grave fever, and notably from typhoid fever. 

In certain cases gangrene is accounted for by the previous pro- 
duction of an arteritis, which, obliterating the principal vessel of a 
limb, abolishes the resistance of the parts depending upon it. Some- 
times arterial alteration is due to a localization of the agent of the 
principal disease; oftener it depends upon a secondary infection. It 



INFLAMMATION 271 

is generally streptococcus that is met with, and this microbe may be 
found in the condition of purity in the vascular clot and the sphace- 
lated tissue. 

In other instances it is a chronic arteritis which, by a similar 
mechanism, causes gangrene; by producing obstruction of a blood 
vessel it permits the development of the skin microbes. Such par- 
ticularly is the process which explains senile gangrene. The focus 
comprises various bacteria, some of them common, others less com- 
mon, as was the one found by Tricomi in a case of this kind. 

Analogous considerations are applicable to mucous membranes. 
In the mouth the gangrene called noma, which is to-day extremely 
rare, occurs in consequence of infectious diseases, especially of mea- 
sles, attacking weak and poorly kept children. The lesion is occasioned 
by slender bacilli (Schimmelbuch, Babes), more frequently by strepto- 
cocci. It is to the same common bacteria, to ordinary pyogenic 
microbes, and to saprophytes that the patches of sphacelus often 
observed in grave diphtheria cases are to be attributed. In gangrenous 
parotidites Grirode has found the pneumococcus associated with a 
slender bacillus. 

The respiratory apparatus is quite frequently attacked; necrotic 
laryngites have been noted during convalescence from serious infec- 
tions, measles, and typhoid fever. The lung especially deserves to be 
studied; it may be the seat of two orders of lesions. In a certain 
number of cases gangrene reaches the bronchial terminations ; this is 
gangrenous bronchitis, the curable gangrene of the bronchial terminations. 
In persons suffering with chronic bronchitis, it is noticed that at a 
certain moment the expectoration and breath assume a characteristic 
odour, but the general condition remains good; the lesion is superfi- 
cial, and is easily cured under the influence of eucalyptus and hypo- 
sulphite of soda. As to the microbes encountered, they are staphylo- 
cocci, streptococci, pneumococci, a long, spore-bearing bacillus de- 
scribed by Lumnitzer, at times higher parasites, such as leptothrix, 
oidium, and actinomycetes. 

The same microbes, although the evolution be different, are met 
with in 'parenchymatous gangrene of the lung. These are pneumo- 
cocci, streptococci, tetragenus, leptothrix, spirilla, and agents of putre- 
faction. There are certain cases where bacteriological examination 
reveals the exclusive or predominating presence of a streptococcus or 
of Staphylococcus aureus. With the latter microbe Bonome has been 
able to reproduce in the rabbit gangrenous foci, which he quite rightly 
compares to anthrax of the lung. In other cases streptococci have 
almost exclusively been found. 

The bacteria multiplying in a morbid focus increase in virulence, 



272 INTRODUCTION TO THE STUDY OF MEDICINE 

and when once excited they may reach a certain number of individ- 
uals. In this way small epidemics are developed, notably in hospital 
wards. But what well demonstrates the part played by accessory 
causes is the fact that individuals with previous lesions of the lung 
are the only ones attacked. 

It is very important to know that, in a certain number of cases, 
the microbes of the gangrenous focus possess no virulence for ani- 
mals. The injection into rabbits and guinea pigs of liquids 
derived from pulmonary gangrene and containing numerous bacteria 
does not often produce any disturbance. Therefore it seems that, 
once set in motion, the process continues despite the weakening of 
the pathogenic agents, which, although capable of causing death in 
a diseased organism, lose all action when they are transported into a 
normal body. 

The study of pulmonary gangrene has made especially prominent 
the part played by predisposing causes. Cachexias, diabetes, chronic 
alcoholism, and inhalation of deleterious gases favour the development 
of the gangrenous process. The latter may develop at once, or may 
be consecutive to another pulmonary lesion. From Laennec to Gri- 
solle, it has always been admitted that pulmonary gangrene should not 
be considered as a consequence of simple pneumonia. Authorities 
have endeavoured to find signs of differentiation between the two pro- 
cesses, such as more diffuse pain in the side, more intense dyspnoea, and 
more marked prostration. The distinction was subtle, and has not 
been confirmed. It is to-day admitted that the pneumonic form of 
pulmonary gangrene is in reality a pneumonia terminated in gan- 
grene. The statistics of Middlesex Hospital are very interesting in 
this regard. Out of thirty-four cases of pulmonary gangrene, we find 
that the process occurred fourteen times in consequence of simple 
pneumonia, nine times consecutively to cancer of the neighbourhood, 
and notably to a cancer of the esophagus, six times in the course of 
chronic pneumonias, four times as the result of embolism, twice in 
dilatation of the bronchi; lastly, in the other three cases, it was con- 
secutive to cerebral hemiplegia, aneurism of the aorta, and tubercu- 
losis of bronchial ganglia. To complete the etiology, we must add 
gangrene of traumatic origin and that which supervenes, notably in 
insane persons, when a bolus of food charged with microbes penetrates 
into the respiratory passages. 

In cases of embolism, it is often a question of transportation of 
microbic agents started from a gangrenous focus toward the lung. 
The process is easy to comprehend; the secondary focus is identical 
with the primary one. But the latter may be simply suppurated: If 
the pulmonary lesion becomes gangrenous, it is because it is invaded 



INFLAMMATION 273 

secondarily by saprophytes, which penetrate with the air and add a 
putrefactive process to the pyogenic. 

A gangrenous focus developed in the lung may reach the pleura 
by propagation. In other cases gangrenous pleurisy will follow a 
pulmonary abscess, the opening of a tubercular cavity, or as a conse- 
quence of the proximity of a tracheal, pulmonary, and especially 
esophageal cancer. Again, it may be consecutive to suppuration of 
some distant organ — the liver, the spleen, or the kidney. There is 
observed in all these cases the development of a sanious, brownish, 
fetid exudation, comprising the various microbes which we have already 
seen in the lung. In other cases gangrenous pleurisy may be caused 
by known microbes — to Proteus vulgaris or to Bacillus coli. 

The abdominal portion of the digestive canal is rarely attacked by 
gangrene; the superficial necroses of the gastrointestinal mucous 
membrane are hardly deserving of this name, except in certain cases 
of dysentery. The true intestinal gangrenes are those that recognise 
a mechanical cause: internal or hernial strangulation permits the 
invasion of the walls by the numerous microbes of the digestive tube 
and speedily ends in mortification. 

As pulmonary lesions frequently extend into the pleura, so intes- 
tinal lesions are often followed by a putrid peritonitis. They may 
also give birth to emboli, which locate themselves in the liver and 
there provoke gangrenous abscesses, as is at times observed in the 
course of dysentery. 

Of the other varieties of gangrene, it is convenient to also cite the 
swift gangrene of the penis, which may cause the death of the organ 
within a few days. The bacteriology of this frightful affection is not 
known. 

Division of Gangrene. — Clinically, two forms of gangrene are 
admitted — dry gangrene and moist gangrene — which are related to each 
other by numerous intermediaries. In dry gangrene, putrefaction is 
less intense and the odour much less marked. Such is the case 
in senile gangrene and certain forms of pulmonary gangrene in 
diabetes. 

Chemical analyses have shown that dry gangrene differs from 
moist gangrene in the smaller amount of water and greater amount 
of carbon. The odour of the foci is due to the presence of volatile 
fatty acids, butyric acid, and especially valerianic acid, and of gases, 
ammonia, and sulphuretted hydrogen. Besides these odorant matters 
are found leucine, tyrosine, and particularly ferments that seemingly 
play a very important part. There is one, analogous to trypsine, 
which digests elastic fibres, and this explains why they are often want- 
ing in the expectoration. 



274 INTRODUCTION TO THE STUDY OF MEDICINE 

Of the various known or unknown substances contained in a gan- 
grenous focus, some are absorbed and produce the grave phenomena 
attending the process. It is, as always, a true intoxication of the 
organism; the general as well as local manifestations of gangrene are 
explained by the action of the secretions and the microbic fermen- 
tations. 

Infectious Nodules 

In suppuration, as well as in gangrene, it is a question of de- 
structive inflammatory process, without any tendency toward organi- 
zation. When infection is less violent, the round cells proceeding 
from the tissues or emigrating from the blood vessels remain living, 
agglomerate, and constitute little nodules. The latter, in a great 
number of cases, are not visible to the naked eye; it is the microscope 
that reveals their presence in the bosom of principal organs — e. g., the 
liver, spleen, kidneys, and lungs. They form small embryonal produc- 
tions, which seem to have developed around a microbic colony; but 
it is not the microbe as a morphological element that acts, since the 
same lesion may be produced experimentally by injections of toxines. 

When the nodule is voluminous and becomes visible to the unas- 
sisted eye, it appears under the aspect of granulations that are di- 
visible into two groups : pseudo-typical or nontypical tubercles, which 
may be produced by the most varied agents, by inanimate foreign 
bodies as well as by living parasites, animal, vegetable, or microbic; 
and true tubercles, which are referable to Koch's bacillus and are 
specific inflammatory nodules. 

TUBEECLES 

Anatomical Characters. — Leaving aside the history of pseudo- 
tubercular granulations, let us consider the development of true tuber- 
cles — that is, those caused by the bacillus of Koch (page 109). 

From an anatomical standpoint, the tubercle presents itself under 
three different aspects: gray granulation, Laennec's tubercle, and 
caseous mass. 

Gray granulation is represented by small, hard, protruding, non- 
enucleable nodosities, often surrounded by a reddish vascular zone. 
Their dimensions vary from 0.5 millimetre to 2 or 3 millimetres; at 
first translucent, they subsequently become opaque and yellowish. 

Laennec's tubercle is more voluminous; it is a round, gray or 
yellow mass, having the volume of a pea, a hazelnut, or even of a 
walnut. 

The caseous masses are greenish-yellow deposits, presenting the 
aspect of certain cheeses, notably of Koquefort cheese. 



INFLAMMATION 275 

These lesions, differing in their macroscopic characters, are con- 
stituted on the same plan; they result from the fusion of several ele- 
mentary lesions designated under the name tubercular follicles. 

The main characteristic of a tubercular follicle is not such or such 
a cellular element, but the mutual arrangement of the various ele- 
ments entering into its constitution. 

Theoretically, a tubercular follicle is formed of three zones. In 
the centre is found a giant cell, the Riesenzelle of German authors. 
Eound or polygonal in shape and provided with numerous projections, 
this nodule contains 20 to 30 oval and nucleolated nuclei, disposed in 
wreath form in its periphery. 

The second zone is composed of epithelioid cells, quite voluminous, 
with an abundant and somewhat granular protoplasm. 

The peripheral zone is represented by embryonal round cells with 
voluminous nucleus. These cells are very numerous and crowded 
together. 

The various cells constituting the elementary tubercle are united 
by an intermediary reticulum of a fibrillary nature. Throughout the 
whole extent of the neoplasm no blood vessel is found, and this is a 
fact of great importance. 

The elementary follicle is not always complete. At first but a 
mass of round cells is found; at a more advanced period the epitheli- 
oid cells may be wanting. 

The bacilli are encountered in great number in the giant cells ; some 
are well coloured, others are colourless or surrounded by a cap- 
sule. The epithelioid cells often contain one or two of them, but 
they succumb when a greater number of bacilli penetrate into their 
interior. 

To constitute the various lesions visible to the naked eye, several 
follicles unite and come to fusion; the agglomeration thus formed 
represents an individual the centre of which degenerates. A vitreous 
degeneration at first appears ; the cells become homogeneous, unite, and 
form a translucent and fissured mass ; then the mass becomes opaque. 
This is caseous transformation, in which morphological elements are no 
longer perceived, not even bacilli. Around this mass there will again 
be found the characteristic lesions, the follicles, or the giant cells. 
So, simply by means of histological examination, Grancher and Thaon 
have been able to re-establish the unity of tuberculosis, which the 
studies of Virchow and of Reinhard seemed to have caused to be aban- 
doned. At present there is no longer any doubt in this respect. Ville- 
min has demonstrated that caseous masses as well as granulations 
give rise to the development of a miliary tuberculosis when inoculated 
into animals. The discovery of Koch has completed the demonstra- 



276 INTRODUCTION TO THE STUDY OF MEDICINE 

tion by permitting the detection of the same bacillus in the various 
anatomico-pathological productions. 

The cells entering into the constitution of the tubercle have been 
considered by some to arise from the fixed cells of the invaded tissue 
(Baumgarten), and by others to be migratory cells. The latter theory, 
sustained by Koch and by Metschnikoff, is now tending to prevail. It 
seems, however, somewhat too exclusive. Histologically, all cells unite 
to form the tubercle. As regards the phagocytic struggle against the 
germ, the principal action is referable to the mesodermic elements — 
namely, to the fixed cells of connective tissue and to 'leucocytes. The 
polynuclear leucocytes are the first to arrive, but they rapidly die and 
are replaced by mononuclear leucocytes, some of which are trans- 
formed into epithelioid cells. 

As to the giant cell, it is produced either by the hypertrophy of a 
leucocyte, whose nuclei then increase in number and form a wreath 
at the periphery of the element, or by the coalescence of several cells. 
Finally, in certain cases the aspect observed is due to the penetration 
of leucocytes into a mass of degenerated protoplasm. 

Thus constituted, the tubercle progresses toward caseation; it may 
then soften and open exteriorly. In other cases it undergoes fibrous 
or calcareous transformation. This is a mode of healing which is 
expressed by a simple cicatrix. 

Localization and Evolution of Tubercles. — Tuberculosis appears in 
man under very different clinical aspects. Pathogenically, the mani- 
festations that are observed may be grouped under three headings : 
lesions by inoculation, produced at the point where the bacillus enters 
the organism, lesions by propagation, and lesions by infection. In 
the last-named case generalization takes place through the blood; it 
is the hematogenic tubercles which, contrary to the preceding ones, 
evolve from within outward. The principal tuberculosis of inocu- 
lation is precisely the manifestation that is most frequently observed : 
common pulmonary tuberculosis. The bacilli introduced with the 
inspired air, generally protected by the organic particles containing 
them, ingraft themselves in the apices of the lungs. This localization 
is to be attributed to the limited expansion of the thoracic cage in the 
upper parts, and, according to Hanau, especially to the weakness of 
expiratory movements. 

The pulmonary foci, largely communicating with the exterior, are 
invaded by a considerable number of bacteria, the effects of which are 
added to those of the principal agent. There occur streptococcus, 
staphylococcus, pneumococcus, tetragenes, colon bacillus and pneumo- 
bacillus, Micrococcus pneumonia (Ortner), etc. All these agents 
work to the destruction of the lung, to the formation of cavities ; the 



INFLAMMATION 277 

soluble products which they produce play a considerable part in the 
appearance of cachexia and in the development of hectic fever. 

The other parts of the respiratory tracts are reached with more 
difficulty than the lungs. Primary tuberculosis is exceptional in the 
nasal cavities and quite rare in the larynx. If the current of air 
passes through the mouth, protection against microbes is still suffi- 
cient, and even though the tonsils often contain bacilli at their sur- 
face, they are very rarely affected by them. 

Next to the respiratory, the digestive apparatus is the most ac- 
cessible to the bacillus. In most cases, however, the intestinal lesions, 
as those of the mouth and the larynx, are secondary, and are to be 
accounted for by the passage or deglutition of expectorations. In the 
statistics published by the Anatomico-pathological Institute of Mu- 
nich, out of 1,000 tuberculous individuals, we find 566 cases of sec- 
ondary tubercular lesions of the intestine, and only 19 of primary 
lesions. As the aliments are to be accused in the latter case, this 
etiology is rare in the adult, and more frequent in children who may 
be nourished with cow's milk containing bacilli. 

The existence of intestinal tuberculosis may be looked upon as 
proved when bacilli are found in the stools; since, in the majority of 
cases, the microbes swallowed do not pass into the faecal matters if 
the intestine is intact. The diagnosis is reached also by the presence 
of blood in the stools. In cases of tuberculous ulcerations not a week 
passes without some blood being found in the stools. 

Inoculations may also be produced in the skin. The results are 
local lesions of little virulence, containing few bacilli and manifesting 
hardly any tendency to generalization. Often primary, these lesions 
are sometimes due to a secondary inoculation. In a person suffering 
from common tuberculosis, a particle of expectoration may be acci- 
dentally deposited upon a slight abrasion; in other cases, a cutaneous 
tuberculosis is developed around a tuberculous fistula. 

As is known, cutaneous tuberculosis assumes several forms. We 
may mention the anatomical tubercle ; tuberculous lupus ; perhaps ery- 
thematous lupus, although the last one does not present the histo- 
logical structure of tubercle, and no bacilli have thus far been found 
in it; warty tuberculosis of the skin, which is mostly observed in the 
hands and fingers ; and, finally, cutaneous foci. In profoundly affected 
tuberculous patients, auto-inoculation has been seen to be followed by 
rebellious ulcerations upon the tongue or the lips, and in cases of in- 
testinal or genito-urinary tuberculosis, in the anus, in the vulva, and 
in the penis. It is a kind of tuberculous chancre, analogous to that 
observed in animals experimentally inoculated. 

Finally, there remains the genito-urinary apparatus, which may 



278 INTRODUCTION TO THE STUDY OF MEDICINE 

also be invaded primarily. In the man, the manifestations generally 
begin in the head of the epididymis, whence the infection spreads suc- 
cessively into the testicle, cords, vesicles, prostate gland, and bladder. 
At times the bladder or the prostate is reached primarily. In women, 
the lesions mostly affect the Fallopian tubes, then the ovaries, and the 
uterus. In both sexes the bacilli may make their way from the blad- 
der to the kidney, and there produce caseous masses and a destructive 
process extending from the papillae toward the cortical substance. 
This aspect permits a distinction between ascending hematogenic and 
renal lesions. But it is to be noted that genito-urinary localizations 
that are met with in 1 out of 50 autopsies are in most cases due 
to a hematogenic origin. 

In short, primary or secondary foci of inoculation may be observed 
in any part of the organism exposed to the contact of the external 
world. The bacilli, being generally transported by the air, in most 
cases invade the respiratory passages ; the digestive apparatus is more 
rarely reached, at least in the adult; the skin is quite frequently 
affected, while primary tuberculosis of the genito-urinary organs is 
extremely rare. 

The focus thus developed may remain isolated, constituting a local 
lesion, often curable. In other cases it causes inflammation in the 
neighbouring parts. In the case of organs like the lung, the intestine, 
the Fallopian tubes, or the seminal vesicles, the adjacent serous mem- 
brane may soon be invaded and present manifestations so intense as 
to dominate all the morbid process. 

Nothing in this connection is as instructive as the history of 
pleurisy. 

The investigations of Landouzy, Kelsch and Vaillard, and those 
more recent of Le Damany, have demonstrated that serous pleurisies, 
except those depending upon a subjacent pulmonary lesion, are always 
of a tubercular nature. The liquid contains only few bacilli, and these 
not constantly; hence its inoculation into guinea pigs rarely produces 
tuberculosis. On the other hand, it quite frequently contains ordinary 
bacteria, whose presence does not seem to very much modify the evo- 
lution of the process. 

Tuberculous pleurisy often assumes a purulent form. The affec- 
tion is remarkable for its long duration, for the little reaction it pro- 
vokes, and for the possibility of a chylous transformation. Bacteri- 
ological examination is of great diagnostic importance, since by these 
means it is possible to decide the tuberculous nature of any empyema 
in which no ordinary pus cocci are present. 

The peritoneum, like the pleura, is frequently reached by the tuber- 
culous process. If, in some cases, the propagation is easily followed- 



INFLAMMATION 279 

up, and if the lesions of the serous membrane have their origin in 
previous alterations of the alimentary canal or genital organs, in other 
cases the peritoneal manifestations seem to be primary. The intes- 
tinal route of entrance is cicatrized and can no longer be found, even 
by an attentive examination. 

Tuberculosis may not only propagate by contiguity into the serous 
system, but also by the circulatory system — lymphatic or sanguineous. 

Baumgarten considered as a law the formation of a local lesion at 
the point where the tubercle bacillus penetrated into the organism. 
This conception, which is for the most part true, suffers from excep- 
tions. Thus is explained the passage of the bacilli into the lymphatic 
system from the respiratory tract and from the alimentary canal, and 
their apparently primary localization in the lymphatic glands. Cer- 
vical adenopathies, so frequent in young subjects, develop without our 
being able to find the entrance of the pathogenic agent. 

It is chiefly in the bronchial glands that this fact occurs. In chil- 
dren it is not infrequent to observe very intense tracheo-bronchial 
adenopathies, with caseous swelling, while the most attentive examina- 
tion fails to reveal the slightest pulmonary alteration. In some cases 
the evolution is the reverse of what might have been supposed: the 
bacilli, having traversed the pulmonary tissue without leaving any 
trace, reach the glands and there produce extensive lesions and sec- 
ondarily invade the lung. In such cases pulmonary tuberculosis is 
consecutive to ganglionic tuberculosis. 

Until recently it was believed that facts of this kind are observed 
only in children. As a result of the researches of Loomis and Pizzini, 
it is now known that in the adult apparently normal bronchial glands 
may contain Koch's bacilli. It is hardly necessary to say that this 
important fact may explain many cases of tubercularization of obscure 
mechanism. 

The same thing may be true with regard to the mesenteric glands, 
at least in children, since Pizzini has never found the bacilli in these 
glands in the adult. In children, on the contrary, mesenteric phthisis, 
or, as it was formerly called, tabes mesenterica, is very frequent, and 
may develop without any appreciable lesion in the intestine. Ex- 
perimental pathology furnishes similar facts. In the guinea pig, mes- 
enteric tuberculosis may follow the ingestion of tubercle bacilli with- 
out any intestinal lesion. 

In other cases the bacilli directly penetrate into the blood circula- 
tion, generally after having occasioned a phlebitis, which explains the 
dissemination of the pathogenic agents. Here two results are pos- 
sible: The microbes, arriving in small numbers and finding the 

organism sufficiently resisting, may locate themselves in some organs ; 
19 



280 INTRODUCTION TO THE STUDY OF MEDICINE 

or, in great numbers invading an organism incapable of destroying 
them, they may spread throughout the economy and give rise to 
a general disease, evolving as a pyrexia — namely, acute miliary tuber- 
culosis. 

In the former case there may be found but a single focus (some- 
times a bone only is affected, or an articulation, or a viscus, like the 
testicle, easily explored). If the initial lesion of the lung has been 
slight enough to heal, there will be found a focus apparently primary. 
In other cases it is an ordinary tuberculous individual in whom vari- 
ous organs have been invaded. The liver is almost always attacked 
at an advanced period of the disease, but its lesions are not generally 
appreciable except under the microscope. The spleen is more rarely 
affected. The kidney is quite often attacked, and this hematogenic 
tuberculosis is expressed by granulations disseminated in its cortical 
substance, in this way assuming an aspect very different from the one 
presented by ascending renal tuberculosis. 

It is at present admitted that acute miliary tuberculosis is almost 
always consecutive to a primary focus — i. e., to a cheesy mass, which 
must be looked for with great care at the autopsy. The penetration 
of the bacilli is preceded, as already stated, by a specific phlebitis. 
Weigert was the first to call attention to this mechanism and to show 
the existence of a tuberculous infection, generally affecting the pul- 
monary veins and explaining the propagation of the bacilli by a series 
of microbic emboli. In some rare cases an artery has played the same 
role (Koch). 

The bacilli, thus thrown into the circulation, have sometimes been 
recovered in the blood. Villemin proved the virulence of this liquid, 
and Weichselbaum, Meisch, Lustig, and Eutimeyer demonstrated the 
presence in it of the specific agent. The germs deposit themselves in 
all the organs and tissues, and, according to a great number of acces- 
sory circumstances, lodge preferably in one or several organs, which 
in part explains the different clinical forms observed: typhoid, gas- 
tric, latent, bronchial, suffocating, pleural, peritoneal, meningeal, artic- 
ular, and renal form. 

In short, aside from the very rare cases of congenital tuberculosis, 
the various modes of tuberculous infection may be easily classified in 
the following manner : 

1. Tuberculosis by inoculation, occupying the respiratory passages, 
more rarely the digestive canal, genito-urinary apparatus, skin, and 
exceptionally the conjunctiva. 

2. Absence of lesions at the point of entrance, or presence of a 
minute, scarcely perceptible, lesion. In this case secondary localiza- 
tions are considered as primary. 



INFLAMMATION . 281 

3. Secondary localizations, whether with or without appreciable 
primary lesion. The secondary localizations are divided into three 
groups : 

a. Secondary tuberculosis by propagation. The most frequent 
types are represented by tuberculous pleurisy or peritonitis. In some 
cases the propagation reaches the osseous system, the biliary passages, 
and, in case of cutaneous fistula, the skin. 

b. Secondary tuberculosis through lymphatic infection, character- 
ized by adenopathies which seem primary and most often occupy the 
cervical region, where they suppurate quite frequently, and the tracheo- 
bronchial or mesenteric glands. In the latter case the affection has 
been described under the name tabes mesenterica. 

c. Secondary tuberculosis through blood infection. This is hemato- 
genic tuberculosis, explained by the presence of a specific phlebitis or 
arteritis; it is expressed either by an external lesion, or by a mono- 
visceral or polyvisceral localization, or by a generalized infection, acute 
miliary or granular tuberculosis. 

Tuberculosis of Animals. — Tuberculosis constitutes the greatest 
scourge not only for man, but also for the animals surrounding him — 
namely, mammals and birds. 

Among mammals, those most frequently affected are the Bovida?; 
the proportion rises to 3 or 4 per cent in the slaughterhouses of the 
great cities of Europe. The lesions may be reduced to three principal 
types. Sometimes it is a generalized miliary tuberculosis; in this 
case the meat is seized. Sometimes it is a local lesion affecting an 
organ or gland or both; the diseased part is then cut off and the re- 
mainder is sold. Sometimes — and this is most frequently the case — it 
is a pulmonary lesion similar to the human. It appears under the 
form of voluminous masses, often infiltrated with calcareous salts ; in 
certain cases a whole lobe is involved, weighing 5, 6, and even 10 kilo- 
grammes. In cases of pulmonary tuberculosis, police regulations order 
the seizure of the affected parts and authorize the sale of the meat. 

The most important lesion of local tuberculosis is that of the 
mammary glands, since the milk then contains bacilli. Fortunately, 
however, mammary tuberculosis is rather infrequent, and, as in other 
cases, the bacilli but rarely pass into the milk, the danger of contami- 
nation through this secretion seems to have been somewhat exagger- 
ated. 

Tuberculosis, rare in the sheep and the goat, is frequent in the 
pig, where it varies between 0.1 and 1 per 1,000. The horse is rarely 
affected. Contrary to an old opinion, the small rodents, such as 
rabbits and guinea pigs, although very apt to contract the disease by 
inoculation, are almost never attacked spontaneously. 



282 INTRODUCTION TO THE STUDY OF MEDICINE 

Among domestic animals, the monkey, the cat, and especially the 
dog, must be cited. 

Since the careful investigations of Cadiot, we know that tuber- 
culosis is frequent in the dog, but it is not always easily recognised, 
as the lesions often appear under the form of cancer. The confusion 
is easy to understand, as microscopic examination may reveal a struc- 
ture similar to that of cancer. These facts are important to know, for 
the dog may serve to transmit tuberculosis through his saliva, and 
especially by his urine, which is often rich in bacilli. 

To-day the world agrees in considering all cases of tuberculosis in 
mammals as due to the same microbe. In consequence of some ex- 
perimental researches, it was believed that tuberculosis of birds de- 
pended upon a special agent, a bacillus of a particular species. This 
opinion, which has been the subject of much lively discussion, seems 
to have been finally abandoned. The avian bacillus is nothing but a 
special variety. It will be considered separately in the Gallince and in 
the Psittaci. 

Tuberculosis of the fowls (Gallince) is very frequent, since it forms 
one tenth of the total mortality of aviary birds ; it is spread through 
the excrements, which are rich in bacilli. The infection takes place 
by the digestive canal, and is expressed by numerous granulations in 
the liver and spleen. The lesions thus developed are easily inoculated 
into the rabbit, but with more difficulty into the guinea pig. Eecipro- 
cally, tuberculosis of mammals, despite the contrary assertions of 
writers, may be transmitted to chickens. In accordance with the re- 
sults of experimentation, inquiries demonstrate that the Gallince are in 
most cases contaminated by the expectorations of tuberculous persons. 

The histological study of avian tuberculosis leads to quite unex- 
pected results. The tubercle has a special structure, different in ani- 
mals akin to each other, like the chicken and the pheasant. In the 
chicken the lesion consists of a vitreous mass bordered by epithelioid 
cells; in the pheasant it is an accumulation of epithelioid cells lim- 
ited by a ring of connective tissue, which becomes infiltrated with 
amyloid matter. 

In the Psittaci tuberculosis is a frequent affection, generally of 
human origin, which in most cases is expressed by cutaneous lesions; 
on the head are seen vegetations, sometimes horns 2 and even 5 centi- 
metres long. At times the lesions occupy the claws, and produce 
deformities similar to those described as gout of birds. 

The bacilli are found in great numbers in the cutaneous produc- 
tions, saliva, nasal liquid, and excrements; they possess very great 
virulence for the guinea pig. So tuberculous parrots represent a very 
serious danger for man. 



INFLAMMATION 



283 



Finally, there has recently been described a tuberculosis of fish, 
proceeding from another variety of tubercle bacillus. But these are, 
at any rate, three varieties of one and the same species. 



NONTUBERCULOUS NODULAR LESIONS 

Nodular lesions are observed in a great number of infections. In 
syphilis we meet with gummatous productions which in some respects 
recall tubercle. We shall not dwell on these lesions, or on those of 
glanders, leprosy, or fungoid mycosis. They are well known and 
everywhere well described. Finally, there exists a series of very dis- 



r 



o 

Q 

& 

w 
Ph 



By inanimate 
substances. 



By animal 
parasites. 



By vegetable 
parasites. 



Of bacterial 
origin. 



Cantharides, lycopodium, Cayenne pepper (Martin). 

Oyster scales (Cornil and Toupet). 

Stony cells of pears (Hanau). 

Ollulanus tricuspis. 

Pseudalius ovis pulmonalis. 

Strongylus vasorum. 

Strongylus rufescens. 

Distome. 

Oospora bovis or actinomyceta. 

Oospora farcinosa. 

Oospora asteroides. 

Mucor. 

Aspergillus f umigatus. 

Aspergillus glaueus. 

Oidium albicans. 

Coccian tuberculosis of the cow (Toussaint). 

Zooglceic tuberculosis (Malassez and Vignal). 

Bacillary pseudo-tuberculosis (Charrin and Roger). 

Pseudo- f of the S uinea Pig (Zagari). 
tuberculosis J of the rabbit (Dor), 
(zoogloeic?) of the hare (Megnin and Mosny). 

^ of the antelope (Cornil and Toupet). 
Fetid bacillary pseudo-tuberculosis (Parietti). 
Bacillary pseudo-tuberculosis of sheep (Preisz and Guinard). 
Bacillary pseudo-tuberculosis of oxen (Courmont). 

of Du Cazal and Vaillard. 

of Hayem and Lesage. 

of J. Courmont. 

of P. Courmont. 



Human bacillary 
pseudo- 
tuberculosis 



similar facts, which have been embraced under the name pseudo-tuber- 
culosis. In this way are designated all lesions which are characterized 
by the production of granulations whose macroscopic aspect recalls 
that of tubercle. The most diverse causes may give rise to them. 
These are sometimes inanimate substances, more often animate para- 
sites, such as strongylus; comparatively highly organized vegetable 
parasites, like Aspergillus f umigatus or actinomycetes, and finally 



284 INTRODUCTION TO THE STUDY OF MEDICINE 

microbes. The first example of microbic pseudo-tuberculosis without 
Koch's bacilli was published by Malassez and Vignal under the name 
zooglceic tuberculosis. This affection, which, it seems, had already 
been perceived by Toussaint, has since been well studied. At the same 
time numerous observations regarding man and animals have been 
brought together which seem to establish the existence of several vari- 
eties or species of pseudo-tuberculosis. But, following the descrip- 
tions, it is not always easy to classify the published facts. 

The tabular representations on page 283 will show the great num- 
ber of pseudo-tuberculoses actually known. 

Among the vegetable parasites that may produce lesions similar to 
tuberculosis a special place is to be given to actinomycetes (page 
113). Its introduction into the organism sometimes provokes a spe- 
cial suppuration characterized by the presence of yellow grains, and 
sometimes the production of tumours similar to sarcoma. 

Very frequent in Bovidce, where it is encountered in the proportion 
of 5 per cent (Russia, Germany), 8 per cent (England), 1 per 1,000 
(Lyons), 0.7 per 1,000 (Paris), actinomycosis is not absolutely rare in 
man. Contamination occurs by contact of diseased animals, more 
often as the result of penetration beneath the skin or in some mucous 
membrane of a spike of grain or barley on which the parasite vege- 
tates. It is mostly about the mouth that infection takes place; it is 
favoured by the presence of carious teeth. 

According to its location, the parasite gives rise to various mani- 
festations. There have been described cervico-facial, thoracic, abdom- 
inal, cerebral, cutaneous, and pyagmic forms. The phenomena recall 
those of tuberculosis or syphilis. Confusion with the latter disease is 
easy, as in both cases iodide of potassium exerts a specific action. 

The clinical analogy with tuberculosis is confirmed by bacteriology. 
We have already cited numerous researches tending to demonstrate 
that the bacillary form of the tubercular microbe is but a transition 
form, and that in certain conditions the parasite assumes a special 
aspect, similar to that of actinomyces. 



CHAPTEE XV 
SEPTICEMIA AND PYEMIA 

Definition of the terms septicaemia, pyaemia, bacteriaemia, bacterio-toxaemia— 
Cryptogenetic, consecutive, and secondary bacteriaemia — Septicaemic forms of 
infections or specific septicaemia — The agents of septicaemia and pyaemia — Ana- 
tomical distinction between the two processes; clinical and bacteriological 
analogies — Etiological division of septicaemias and pyaemias — Principal clin- 
ical characters — Evolution — Importance and frequency of attenuated forms. 

Definition and Division of Septicaemia and Pyaemia. — Septicaemia 
and pyaemia constitute two morbid processes, which must be drawn 
nearer and united under the name bacteriaemia. In fact, the patho- 
genic agent tends to invade the entire organism and to develop there 
without causing special lesions (septicaemia) ; or it locates itself in 
certain viscera or tissues and gives rise to the formation of purulent 
foci (pyaemia). In the latter case a considerable number of small 
abscesses are generally found, at the autopsy, occupying the liver, kid- 
neys, lungs, heart, etc. These are designated by the quite improper 
name metastatic abscesses. 

Bacteriaemia must be distinguished from bacterio-toxaemia, in 
which the pathogenic agent remains localized and excites general dis- 
turbances by means of the toxines it secretes. In bacteriaemia there is 
general infection; in bacterio-toxaemia, intoxication. 

Bacteriaemia therefore includes both septicaemia and pyaemia. The 
expression septicaemia, created by Piorry, was applied by him to every 
alteration produced in the blood by septic or putrid matters, whatever 
their origin. After having been employed in most diverse senses, the 
term was adopted by bacteriologists, who have not been able to offer 
any better definition than clinicians. Confusion was further increased 
when the bacillus of gaseous gangrene was called septic vibrio, and the 
disease induced by it gangrenous septicaemia. These inaccurate terms 
led to great errors and nosological confusion. Thus, for example, 
deceived by these words, some authors believed that septicaemia and 
pyaemia should be separated on the ground of the different characters 

285 



286 INTRODUCTION TO THE STUDY OF MEDICINE 

of their pathogenic agents. Following the expressions used by bacteri- 
ologists, they believed that the former of these two processes was due 
to an anaerobic bacillus — i. e., septic vibrio — remaining at the point of 
introduction; the latter to aerobic microbes invading the organism, 
and there producing secondary abscesses. 

A word evidently having no other sense than that given it by an 
author may be employed, provided it be well denned. The term sep- 
ticaemia, then, might be reserved for gaseous gangrene and similar 
processes. This, however, would be a notable departure from the pre- 
vailing tendency, as logically it would be necessary to consider all 
local diseases which kill by intoxication as septicaemia, and also to 
include tetanus, diphtheria, cholera, etc., in this group. In these in- 
fections, as in gaseous gangrene, the microbes remain localized at one 
point, and it is their soluble products that excite general reactions. 
The disease is therefore of a toxic nature. This is why these diverse 
processes constitute a separate group — i. e., bacterio-toxaemia — and 
why gangrenous septicaemia must be excluded from the group of true 
septicaemias. 

Thus limited, bacteriaemia represents a nosological class, which is as 
yet artificial. Nevertheless, its existence may be justified by the fol- 
lowing considerations. 

In cases of septicaemia the microbe is present in every part of the 
organism. It may often be detected in the blood during life, and 
always after death. The lesions are those common to all intense 
infections. The blood is disintegrated and dark in colour; numerous 
ecchymoses are observed in the viscera and tissues. At times hemor- 
rhages are so abundant that the process deserves to be designated as 
hemorrhagic septicemia. The microscope reveals small vascular 
thromboses, cellular degenerations, and occasionally embryonic foci, 
indicating a reactionary tendency on the part of the organism. These 
foci, however, are limited, and are not visible to the naked eye. 

At the end of a variable time, however, the microbes become local- 
ized in certain portions of the economy. Septicaemia then loses the 
character of a general infection, and visceral localizations become 
prominent. Consisting at times of simple inflammatory lesions, the 
secondary foci may, in other instances, undergo purulent transfor- 
mation. Under these circumstances the process is sometimes called 
septico-pyamia, which represents a transition with pyaemia properly 
so called. 

Pyaemia is distinguished from septicaemia by the tendency of the 
infectious agent to localize itself from the beginning in certain vis- 
cera or tissues, and there give rise to the formation of purulent foci. 
The pathogenic agent transported by the blood quickly leaves this 



SEPTICEMIA AND PYEMIA 287 

medium; hence certain authors admit that in true pyaemia the 
microbes are encountered exclusively in the tissues. When they are 
found at the same time in the blood the process is known as septico- 
pyaemia. We will soon see that this last distinction is of a rather 
subtle nature. 

Septicaemia and pyaemia may produce anatomical lesions, and they 
may also be consecutive to some local lesion. According to their 
apparent point of departure, two varieties may be admitted. The first 
is characterized by invasion at once of the entire organism; the point 
of entrance of the microbe and the initial lesion are wanting or remain 
unperceived. Under these circumstances the infection is said to be 
spontaneous or crypto genetic. The latter terms, introduced by von 
Leube and accepted by Jurgensen, is now frequently employed in Ger- 
many. In the second case general infection is preceded by a local 
lesion. Here two events are possible: Sometimes the primary focus 
contains the microbes which will invade the economy, in which in- 
stance bacteriaemia deserves the name consecutive. Sometimes, on the 
other hand, the primary focus is due to specific or nonspecific agents, 
which only prepare a route of entry for the microbe of general infec- 
tion, in which case bacteriaemia is said to be secondary. 

According to the few considerations just presented, we may classify 
the various types of septicaemia and pyaemic infections as follows : 

Classification of Septicemias and Pyaemias 



Primary 



Consecutive. 
Secondary. 



According to their Origin. 
( Traumatic. 



( Cryptogenetic. 



According to their Evolution. 

Without special localization 
(true septicaemias). 

With inflammatory visceral localiza- 
tions. 

With suppurative j Septico-pysemias. 
localizations. ( Pyaemias. 



It may be asked whether general infection is not always consecu- 
tive to a local lesion which in some instances is so minute as to 
escape detection. Such an occurrence is frequent, but the reality of 
primary general infection seems demonstrated by numerous surgical 
observations and experimental researches. Clinically, disturbances 
have been seen to follow an accidental, an operative, or an obstetrical 
wound which seemed perfect. It is the same with animals. When 
an extremely virulent microbe — a certain streptococcus, for example 
— is inoculated beneath the skin, death supervenes from bacteriaemia 
without there being any trace of local lesion. Furthermore, under a 
very great number of circumstances, the microbes located upon or 
within our bodies, notably those of the digestive canal, may penetrate 



288 INTRODUCTION TO THE STUDY OF MEDICINE 

into the economy, and, if the system is sufficiently weakened, it is com- 
prehensible that they may at once create a general disease. In such 
cases it is impossible to find a trace of their passage. No local lesion 
exists. If it were always possible to determine the mechanism of the 
infection, facts of this kind should be grouped under the name auto- 
bactericemia. 

Consecutive general infections, however, are the most frequent and 
important, since they include the great majority of surgical and obstet- 
rical septicaemias and pyaemias. With these must also be included 
certain cases in which the primary lesions are of a medical order — i. e., 
occupying such parts of the organism and affecting such localities as 
to render operative intervention impracticable. 

It is not alone in suppurative lesions that this process is called 
into play. It is of constant occurrence in the course of the most 
diverse diseases. In this way, when an erysipelas or a plain pneu- 
monia terminates in death, the infection nearly always assumes a sep- 
ticaemic form. At the autopsy, and even during life, the microbe — 
streptococcus or pneumococcus — is found in the blood and all the 
organs. 

The same evolution is observable with highly differentiated bac- 
teria. For example, this takes place in anthrax. In man, the bacillus 
produces a local lesion — i. e., a malignant pustule. It too often 
crosses the barrier opposed to it by the organism and invades the entire 
economy. It is then said that the patient has died by anthrax sep- 
ticaemia. It may even happen, at least in animals, that the local lesion 
is wanting. In such cases anthrax manifests itself as a true sep- 
ticaemia. 

It is even said that such or such an infection assumes a septicaemic 
form in cases in which it develops without occasioning its usual mani- 
festations or lesions. Thus, a septicaemic form of typhoid fever has 
been described. It would therefore be easy to extend the limit of 
septicaemias so as to include almost all infections, at least in certain 
forms. 

To avoid the confusion which would result from such a conception, 
we are obliged to arbitrarily designate as septicaemias those bacteri- 
aemias that are due to ordinary agents, and to distinguish those cases 
in which a well-defined agent has from the first or consecutively in- 
vaded the entire organism and behaved as in true septicaemia, as sep- 
ticaemic forms or specific septicaemias. Thus, to take up the examples 
above referred to, we shall speak of a septicaemia with streptococcus 
and a septicaemia with staphylococcus; whereas, if the case be one of 
general infection by the Bacillus anthracis, we shall make use of the 
expressions specific septicaemia or septicaemic form of anthrax. By so 



SEPTICEMIA AND PYEMIA 289 

doing we conform alike to clinical data and to the results of bac- 
teriology. 

We believe it proper sharply to separate the consecutive from the 
secondary infections. The distinction is equally justified by clinical 
experience and bacteriology. In consecutive infections the same 
microbe produces all the lesions. Let us take, for example, a purulent 
infection consecutive to a phlegmon. Clinically, it is the same pro- 
cess that has become generalized. Bacteriologically, the same microbe 
— staphylococcus or streptococcus — is found in the initial phlegmon 
and in the metastatic abscesses. Pyaemia is then said to be consecutive. 

On the other hand, let us assume that a diphtheritic angina exists. 
If the patient succumbs to septicaemia, we may say that this sep- 
ticaemia is secondary, as the latter will be produced by streptococcus, 
while the primary agent has remained localized in the throat. The 
process is one which has been secondarily superadded to the primary. 
Likewise, the arthrites of gonorrhoea may sometimes be produced by 
the gonococcus. Here the process is one of generalization due to the 
main infection, viz., a consecutive bacteriaemia. More often these 
arthrites are due to an infection superadded by a pyogenic agent which 
has simply profited by the urethral lesion and invaded the economy. 
This is a secondary bacteriaemia. 

Bacteriology. — It has seemed to us useful to unite septicaemia and 
pyaemia in one group. Although pathological anatomy sharply sepa- 
rates these two processes, clinical observation justifies their closer 
relation, and bacteriology confirms the results of observation by estab- 
lishing that the same pathogenic agents are concerned in the majority 
of cases. 

There exist a few microbes which thus far have been met with only 
in one of the two processes. This, however, is the exception. What 
is most often detected in cases of septicaemia or pyaemia is, first, strep- 
tococcus, then Staphylococcus aureus, more rarely pneumococcus, pneu- 
mobacillus, or tetragenus. Among the other septicaemia agents we may 
cite the colon bacillus, bacillus of psittacosis, bacillus of hemorrhagic 
septicaemia (important chiefly in animals), Bacillus pyocyaneus, Ba- 
cillus septicus puti&us, Bacillus proteus vulgaris, etc. The agents of 
pyaemia are much more numerous. Besides the microbes already men- 
tioned, we shall note a special bacillus described by Levy. Parasites of 
a higher order, such as actinomyces, might also be cited; also the 
bacillus of glanders, which causes a true specific pyaemia justly de- 
scribed by authors in a separate chapter. 

General Etiology. — From a purely etiological standpoint, sep- 
ticaemias and pyaemias are divided into puerperal or obstetrical, surgi- 
cal, and medical. 



290 INTRODUCTION TO THE STUDY OF MEDICINE 

The streptococcus, which, as we have said, plays the principal part, 
is the almost constant agent of puerperal septicaemia and pyaemia. 
Clinical experience has prepared us for the acceptance of this fact 
revealed by bacteriology. Puerperal fever has more than once been 
contracted by patients treated in proximity to erysipelatous women. 
On the other hand, erysipelas has at times appeared in persons 
who had taken care of puerperal women. Finally, there are cases 
in which the two infectious manifestations coexist in the same subject. 
However, the bearing of these facts should not be exaggerated. 
Women suffering with erysipelas have often been confined without 
developing septicaemia, and erysipelas has appeared a few days after 
confinement and been perfectly cured. 

Contamination occurs mainly from one to another puerperal 
woman. The streptococcus then proves to be much more active, and 
seems to be endowed with special virulence. It is in such cases that 
infection may be transported to a distance through the agency of 
clothing, linen, and instruments. 

Lastly, the infection may appear spontaneously. It is explained 
by an auto-infection due to microbes normally inhabiting the exter- 
nal genitals. 

We shall not dwell upon the causes of surgical infections. Three 
conditions may be present. Sometimes, the wound being soiled by 
germs, general infection is established at once; sometimes a local 
lesion is first produced, which subsequently induces a general infec- 
tion; finally, infection follows a traumatism without there being any 
external wound. Facts entering into this last category are excep- 
tional. W T agner has recorded a remarkable example in a case of 
pyaemia consecutive to a fall upon the hip. 

When bacteriaemia is consecutive to a wound it is not at all neces- 
sary that the latter be extensive. Disturbances have been seen to 
occur in consequence of minute traumatisms. Dandois has reported 
a case in which pyaemia followed a leech bite. It should be remem- 
bered, however, that infection is always favoured by all causes pro- 
ducing great damage and profound attrition of the soft parts. Disin- 
fection of such wounds is difficult, and the microbes find conditions 
favourable for their development in the altered and contused tissues. 
Finally, in surgical as well as puerperal infections, the dominant eti- 
ological factor is the transportation of germs by the hands of the oper- 
ator or through badly sterilized instruments. 

At the present day these are commonplace facts, and need but to 
be mentioned. 

The last group, which belongs to the domain of both surgery and 
medicine, includes the cases in which bacteriaemia is consecutive to 



SEPTICEMIA AND PYEMIA 291 

some old lesions. These are suppurating wounds, oftener profound 
suppurations, whose disinfection is a difficult matter. We have 
already shown in connection with suppuration that, in order to explain 
the generalization, it was necessary to assume a previous modification 
of the organism, probably under the influence of microbic products 
originating from the primary focus. 

We are, of course, unable to cite all the lesions that are liable to 
terminate in a general infection. Cutaneous or superficial alterations 
rarely have this effect, except in the newborn, in whom suppurations 
of the umbilical cord cause an omphalitis permitting microbic gener- 
alization. In adults, suppurations within cavities or the viscera are 
especially liable to give rise to general infection. It is true, however, 
that since the general adoption of antisepsis the number of cases of 
infection is constantly diminishing. In cases of otitis, for example, 
Chauvel found, out of a total of 1,137 observations, but 5 cases of sep- 
tico-pyaemia, only 2 of which proved fatal. 

Likewise, in medical affections there is no constant relation be- 
tween the gravity of the primary lesion and its tendency to gen- 
eralization. Cutaneous suppurations, notably those of smallpox, 
alterations of the tonsils, intestinal ulcerations, lesions of the liver, 
urinary passages, and the lungs, are the most frequent causes of the 
infective process. 

The primary lesion is not necessarily suppurative. Diphtheritic 
or scarlatinal sore throat may open the door to pus cocci. We must 
give a special place to common infections, which are so frequently 
observed in the course of tuberculosis and which modify the progress 
and aspect of the disease. In examining during life the blood of 
patients attacked by febrile phthisis, Jakowski found microbes seven 
times : Staphylococcus aureus, five times, twice in a pure culture, 
twice associated with Staphylococcus albus, once with streptococcus; 
in the other two cases he discovered streptococcus. In an observation 
of Etienne and Specker, tuberculosis was complicated with a sep- 
ticaemia induced by a microbe related to the pneumococcus. These 
secondary infections play a great role in the mechanism of hectic 
fever, and in other cases may give rise to multiple suppurations, puru- 
lent arthritis, and visceral abscesses. 

Lastly, there remains the group of cryptogenetic septicemias, in 
which general infection seems to supervene at once. This group may 
be divided into two secondary groups. At times the initial lesion 
passes unnoticed. During life it is not revealed by any appreciable 
symptom, but none the less it exists, and is found at the autopsy. 
It may be a visceral suppuration, an intestinal ulceration, an old focus 
having its seat in a ganglion, or a suppurative salpingitis, etc. 



292 INTRODUCTION TO THE STUDY OF MEDICINE 

In other cases, on the contrary, the minutest post-mortem exami- 
nation fails to reveal any internal lesion. Infection is produced from 
the beginning. In a good many cases it is explained by a previous 
weakening or decline of the organism. In fact, it is known that, on 
the slightest occasional cause, the germs which multiply upon the 
integuments or mucous membranes invade the economy. It is even 
probable that they constantly penetrate into the tissues under normal 
conditions. But those which enter a healthy organism are rapidly 
destroyed. It is no longer so, however, when the organism suffers 
from the influence of an accessory cause — for example, cold, fatigue, 
or overwork. The part played by overwork seems to us very impor- 
tant, and the clinical cases known under the name overwork fever 
(fievre de surmenage) must be considered as septicemic. Excessive 
muscular work facilitates infection by lessening the alkalinity and 
diminishing the germicidal power of the humours. Infection occurs 
through the skin, perhaps more frequently through the intestinal 
mucous membrane. It is known with what facility germs pass 
through the walls of the digestive tract. Faecal stagnation, during 
only five or six hours, suffices to produce general infection (Arnd, 
Multanowski). It is then probable that a good many infections whose 
point of departure escapes our notice must be referred to an intestinal 
origin. 

However, it must be acknowledged that there are cases which defy 
all explanation. No cause whatever is found permitting us to under- 
stand their development. 

Evolution. — Infection may behave throughout its course as a sep- 
ticaemia without any localization. The characteristics of the disease 
are severe initial chills, high fever, and a very grave general state. 
If the evolution is rapid, death supervenes without any organ being 
especially affected. If the disease be prolonged, visceral localization 
may occur. General manifestations then become less, and the lesion 
which expresses the fixation of the process develops on its own ac- 
count. There exist numerous transitions between pure septicaemias and 
those where general infection, pushed into the background, may become 
so slight as to be hardly noticeable. And yet septicaemia has been an 
intermediary state between the primary lesion and the secondary 
localization in some viscus. Acute endocarditis, nephritis, or hepatitis 
are in many cases but septicaemias with a predominant localization. 

If the visceral localizations of septicaemia are expressed by the pro- 
duction of purulent foci, it is said that septicaemia terminates in 
pyaemia. In other cases pyaemia comes on at once. It is difficult to 
say why, under certain circumstances, a septicaemic agent gives rise to 
suppuration. The consensus of opinion assumes that, in the latter 



SEPTICEMIA AND PYEMIA 293 

case, it is less virulent. Septicaemias seem mostly to be of a toxo- 
infectious nature. They occur when bacteria find in the organism 
conditions favourable for the production of toxines. In contrary 
cases they are in part destroyed, and the proteines of their cadavers 
cause the formation of pus. 

Pyaemias, primary or secondary, are expressed by multiple suppura- 
tions, which sometimes occupy superficial regions — skin or articula- 
tions — sometimes the viscera. The medical pyaemias with articular 
localizations, long confounded with acute articular rheumatism, have 
been described under the name arthrito- suppurative disease and infec- 
tious pseudo-rheumatism. The lesions have a great tendency to local- 
ize themselves in some joints and to induce suppuration and anchy- 
losis. 

Pyaemias with cutaneous and subcutaneous determination are less 
frequent. In the former case infectious erythemata, purpura, pus- 
tules, and bullae full of pus develop ; in the latter case, multiple phleg- 
mons appear. 

It is also to pyaemia that German writers attribute the osteomye- 
litis of adolescents. This conception is perfectly acceptable, as it 
explains the gravity of general phenomena, and, as is often observed, 
their attenuation when localization of the process takes place. Ac- 
cordingly, osteomyelitis would be staphylococcic pyaemia of young 
subjects. 

As to visceral pyaemias, they are too well known to need a study 
here. Multiple abscesses are found chiefly in the kidneys, liver, spleen, 
lungs, and brain; and purulent collections in the serous membranes, 
purulent infiltrations in the heart, etc. It is not rare to see these 
various forms associated. In the ordinary surgical pyaemia foci exist 
simultaneously in the viscera and the joints. 

Attenuated Forms of Septicemias and Pyaemias. — The expressions 
septicaemia and pyaemia immediately suggest the idea of a grave and 
most often fatal process. However, along with the acute forms, we 
must admit a certain number of cases where the process becomes local- 
ized and tends to resolve. At times the manifestations may even be 
ephemeral. Traumatic fever and milk fever are nothing else than 
septicaemic fevers, so innocent that they may pass away within twenty- 
four or forty-eight hours. It is the same with certain urinary fevers, 
which have but a transitory duration. In other instances the evolu- 
tion, which had at first seemed very serious, becomes modified at a 
certain moment. This takes place when a visceral localization occurs. 
In the course of a puerperal septicaemia, for example, the disquieting 
manifestations will decrease and disappear when a phlebitis or a peri- 
uterine purulent focus develops. The lesion seems to be a point of 



294: INTRODUCTION TO THE STUDY OF MEDICINE 

attraction for the circulating microbes, and it is conceivable that cer- 
tain authors, like Dr. Fochier, should have proposed to suppress the 
infectious process by attempting to localize them by means of fixation 
abscesses. 

The same remarks are applicable to pyaemias. While the general- 
ized forms — those, at least, where numerous visceral foci exist — are in- 
evitably fatal, there exist benign pyaemias in which localization takes 
place in a tissue — e. g., in a joint. These cases can be cured after 
surgical intervention. 

In conclusion, along with acute generalized septicaemias it is con- 
venient to admit attenuated forms — transitory septicaemia (milk 
fever); innocent septicaemia with subacute or chronic course; septi- 
caemia with a single secondary localization, suppurated or not ; pyaemia 
with a single or very few localizations. These various forms easily 
terminate in recovery. Even in grave cases the prognosis is not always 
fatal. There are on record cured cases of generalized infections. This 
fortunate result is observed chiefly in septicaemia because the latter 
is not attended by profound cellular lesions. In the case of general- 
ized visceral pyaemia, the attenuation or even destruction of the agents 
is of no consequence. The patient will succumb, not to the infection, 
but to the visceral lesions resulting therefrom. 



CHAPTEK XVI 

EVOLUTION OF INFLAMMATIONS— SCLEROSIS 

Alterations of epithelial cells; their degeneration — Proliferation of epithelial cells 
— Adenoma — Functional disturbances — Reparation of lesions — Sclerosis — Sig- 
nificance of the sclerotic process — Mode of formation of scleroses — Arterio- 
sclerosis; importance of this process; principal clinical forms — Notions of 
therapeutics. 

Alterations of Epithelial Cells. — In the stndy which we have thns 
far made of inflammation, we devoted onr attention especially to the 
elements of connective tissne — namely, elements proceeding from the 
middle layer of the blastoderm. We have seen that these elements 
undergo two sorts of modifications — namely, phenomena of degenera- 
tion, which are not very pronounced, and reactionary phenomena, 
which are very intense and terminate in the production of various 
cells that are found in the exudations. We have also shown that 
proliferation is not a wholly local process. On the contrary, the entire 
organism becomes impregnated in consequence of the absorption of 
toxic products. Modifications also occur in the various tissues con- 
cerned in the production of leucocytes — i. e., in the spleen, lymphatic 
glands, and bone marrow. 

The changes produced in the epithelial cells are of an analogous 
nature, except that, contrary to what occurs with the mesodermic tis- 
sues, degeneration predominates over proliferation. These phenom- 
ena of degeneration are especially marked at the inflamed point, and, 
if the lesion be prolonged, they may be observed in distant parts and 
reach the principal viscera. Here, again, the question is one of a 
toxic process, of absorption from the focus of soluble substances, which 
induce various degenerations in the economy, notably fatty or amyloid 
degeneration. 

In its highest expression, the damage done to the vitality of the 
cells is manifested by the process designated by Weigert as coagula- 
tion necrosis or fibrinous degeneration. The cell is transformed into 
a small, dry, fragmented mass, similar to coagulated fibrine; the 
20 295 



296 INTRODUCTION TO THE STUDY OF MEDICINE 

nucleus disappears, and nothing remains to recall the original 
structure. 

If the inflammation is less intense, a series of degenerations occurs, 
which we shall briefly indicate. First of these is fatty degeneration — 
namely, the production of small drops of fat in the protoplasm of the 
cell. This process, which is very clearly shown in the liver, kidney, 
and myocardium, should not be confounded with fatty infiltration. 
In the latter process a drop of fat is deposited in the cell and crowds 
the protoplasm, but the latter retains its vitality and functional activ- 
ity. In fatty degeneration the protoplasm itself undergoes meta- 
morphosis. 

Fatty degeneration is also indicative of an acute process. In less 
intense grades granular degeneration characterized by a cloudy meta- 
morphosis of the protoplasmic albumin, is observed, also colloid, vacu- 
olated, hyaline, and amyloid degenerations, the latter especially fre- 
quent in the vascular system; mucoid degeneration, and, finally, pig- 
mentary degeneration. All of these lesions will be discussed in a spe- 
cial chapter. 

While these various modifications are produced in the cell, changes 
of no less importance occur in the nucleus. If the process is very 
intense, as in coagulation necrosis, the nucleus disappears; if less in- 
tense, the nucleus atrophies, and in other cases it proliferates. This 
last modification is observed when the inflammation is not too intense, 
and it is also encountered at the periphery of the lesions — i. e., around 
the parts which degenerate and become necrosed. 

Cellular reactions may differ in the same organ, according to the 
system concerned. In the liver, for instance, the toxic or infectious 
substances produce degeneration of the hepatic cells, while the epi- 
thelia of the bile passages proliferate. The explanation is that the 
supporting cells of the excretory ducts are not as highly organized as 
the secretory cells; consequently, they are less delicate and more re- 
sistant. This is why a production of newly formed biliary canaliculi 
is observed along with degeneration of the hepatic cells in certain 
infections of the liver. 

If the inflammation is subacute or chronic, the hepatic cells them- 
selves may proliferate. In this way nodules are formed, the cells of 
which are grouped in such a manner as to constitute small tumours, 
sometimes described under the name adenoma. 

In slow inflammations of the skin and mucous membranes, hyper- 
plasia is also observed. In chronic gastritis, enteritis, or metritis the 
glands become elongated, develop, and form small tumours. In this 
manner are produced adenomata, which constitute a transition between 
inflammations and neoplasms. 



EVOLUTION OF INFLAMMATIONS— SCLEROSIS 297 

The various alterations produced in the inflamed cells modify their 
volume, form, mutual relations, and functional activity. When de- 
generation is predominant, the cell, which at first may be hypertrophic, 
atrophies, and is no longer represented except by small, unrecognisable, 
cuboidal elements. When proliferative reaction predominates, the cell 
grows and hypertrophies. These changes of volume may of themselves 
modify the normal disposition of the tissues. On the other hand, the 
functional disturbances produced hinder the production of the cement 
substance which unites the cellular elements. This lesion, first de- 
scribed by Drs. Landouzy and Eenaut, is especially easy to study in the 
myocardium. The various cells of the myocardium become dissoci- 
ated and undergo segmentation. The process in the liver is probably 
similar to segmentary myocarditis, and explains the dislocation of 
the hepatic elements observed in grave infections of the liver. 

It can readily be understood that these various lesions lead to a 
profound modification of the functional activity of the cells. If the 
inflammation is very intense, function is abolished and secretion is 
arrested or considerably diminished. If, on the other hand, the in- 
flammation is slight, the epithelia are stimulated and secretion is 
increased, but the latter deviates from the normal type. 

In this manner are developed catarrhs characterized by the pro- 
duction of abundant fluids rich in mucine and containing numerous 
altered cells and colloid exudates derived from diseased elements. It 
will suffice to recall what takes place in the stomach, intestine, biliary 
passages, and especially in the kidneys. In the various forms of 
nephritis, for example, the urine contains numerous cells, isolated or 
united in cylinders, or exudations which are moulded in the tubules 
and constitute the so-called hyaline casts. 

Reparation of Lesions. — The alterations we have just indicated 
may resolve and disappear. Separation, however, is seldom perfect; 
for whenever the process attains a somewhat intense character the 
affected cells disappear and are replaced by cicatricial tissue. 

There is a very curious difference between the evolution of trau- 
matic lesions and that of inflammatory lesions. The former are 
repaired with the greatest facility. Experimenters and surgeons have 
shown that the viscera regenerate. In animals it is possible to remove 
large portions of the liver, spleen, or kidneys. In such instances the 
mutilated organs are reproduced according to their normal type. The 
directing idea presiding over the development of the individual seems 
sufficiently strong to assure restoration and a return to the original 
or normal condition. 

The destruction of cells is often much less marked in inflammation 
than in traumatisms. The lesions are less extensive and less consid- 



298 INTRODUCTION TO THE STUDY OF MEDICINE 

erable. In certain cases but a few cells are destroyed ; their reparative 
work seems easier, and yet it does not take place. The directing idea 
seems to have been inactive. 

The paradox distinguishing these two orders of facts may be com- 
pared to that offered by the study of heredity. We have seen that 
accidental traumatic mutilations are not transmitted to the offspring. 
On the contrary, lesions consecutive to functional disturbances are 
generally inheritable. The cause which has induced an anatomical 
alteration by producing a physiological change has been strong enough 
to modify the law of preservation of the ancestral type. That which 
appears so clearly concerning the succession of beings is also applicable 
to the individual. Traumatic lesions are accidents which do not mod- 
ify the normal evolutive type ; they may be repaired in the subject, and 
do not influence his descendants. On the other hand, anatomical 
lesions dependent upon some functional disorder express an impreg- 
nation of the economy by a pathogenic agent; they are responsive 
manifestations resulting from a change in the organic direction, are 
repaired incompletely and with difficulty, and are transmitted by 
heredity. This is a new proof that the great laws which govern the 
life of the individual are the same as those which govern the life of the 
species. 

Reparation takes place through the agency of the cells which have 
proliferated, chiefly the mesodermic and the migratory cells. In this 
way buds are formed which become vascularized. Sometimes the 
appearance of blood vessels is explained by the development of a vessel- 
forming cell, which communicates with neighbouring capillaries by 
means of prolongations. Sometimes solid cords are observed, which 
subsequently become hollow and join the capillaries. Most frequently, 
however, the capillaries themselves send out ramifications toward the 
tissues and re-establish the circulation. 

The cells increase in number through the supply of nutritive mate- 
rials furnished by the newly formed vessels. The differentiated ele- 
ments are reproduced, and clasmatocytes reappear. Finally, the parts 
that can not be reconstructed according to the normal type are re- 
placed by fibrous connective tissue. This is sclerosis. 

Sclerosis 

Well-constituted sclerotic tissue is feebly vascular. It is white, 
hard, resistant, and grates under the scalpel. Sometimes it is exuber- 
ant and gives to the viscera in which it occurs an exaggerated develop- 
ment. Such is the case with hypertrophic cirrhoses. Sometimes it 
appears under the form of a tumour — i. e., keloid. On the other hand,, 
it sometimes manifests a notable tendency to retraction and to diminish 



EVOLUTION OF INFLAMMATIONS— SCLEROSIS 299 

the bulk of the organs. If it occurs in a canal, it causes a progressive 
stricture, as, for example, in the esophagus and urethra. When it 
develops in a viscus, the sclerotic tissue leads to atrophy of the organ. 
The compressed soft parts protrude and impart a granular aspect to 
the organ. This fact explains Laennec's granulations in atrophic cir- 
rhosis and Bright J s granulations in interstitial nephritis. Simul- 
taneously with the evolution of these lesions, the parts that have re- 
mained healthy tend to replace the diseased parts. In this manner 
hyperplasias and compensating hypertrophies are produced which fur- 
ther modify the form of the organ. 

Sclerotic tissue may have other disadvantages. By lining parts 
which should unite, it may become the cause of fistulae; when it de- 
velops in parts anomalously in contact, it may give rise to adhesions. 
In other cases it causes vicious cicatrices and disturbs the func- 
tional activity of the organs. It compresses subjacent parts or it 
narrows the vessels supplying the organs, and thus interferes with 
their nutrition. 

Sclerotic tissue, therefore, fills up the vacant spaces left by degen- 
erated and dead cells. In other words, it is a substitution tissue. 
To a certain extent sclerotic tissue represents a conservative lesion, no 
matter whether it develops, as is generally admitted, at the expense of 
connective-tissue cells — i. e., is preceded by an embryonal stage — or 
progressively through hypertrophy of pre-existing fibres, as in certain 
cases seems undeniable; or, according to the recent views of Retterer, 
as the result of a transformation of ectodermic and endodermic cells. 
However, while it remedies the primary accidents, it at the same time 
becomes the cause of new disturbances. It may be said, therefore, 
that sclerosis is both an end and a starting point. 

Sclerosis is the last stage of all pathogenic causes that have entered 
into the life of the individual, and this explains its great frequency 
in the aged. Exogenous intoxications, acute or chronic intoxications, 
auto-intoxications, including overwork, nutritive disturbances, and, 
above all, arthritism, are justly regarded as etiological factors in its 
production. 

Several of these same causes may induce cellular degenerations 
without sclerosis. In the liver, for example, alcoholic intoxication 
sometimes gives rise to diffuse steatosis, and sometimes it causes cir- 
rhosis. The same is true of infections. For example, tuberculosis 
produces either fatty degeneration, hypertrophic cirrhosis of the liver, 
or an atrophic cirrhosis comparable to that observed in drinkers. 

The different effects produced by the same etiological conditions 
cited in the chapters devoted to degenerations and scleroses are ex- 
plained by the varied degree of power possessed by the pathogenic 



300 INTRODUCTION TO THE STUDY OF MEDICINE 

agent or by a dissimilar responsive aptitude on the part of the or- 
ganism. 

When the cause is very active or the organism weakened, degen- 
eration predominates ; when, on the other hand, the cause is less active 
or the organism more resistant, sclerosis prevails. Tuberculosis 
causes degeneration in predisposed individuals ; in subjects but slightly 
sensitive to this infection; in arthritics, for example, it manifests a 
tendency to produce fibroid changes. The same holds good in regard 
to intoxications. For example, alcohol, when administered in large 
doses, causes fatty degeneration; in small doses it produces cirrhosis. 
It has been possible to produce either of these processes in animals by 
giving similar doses of this poison. In order to obtain degeneration 
or sclerosis at will, all that is necessary is to place the subjects experi- 
mented upon under good or bad hygienic conditions and to furnish 
them copious or insufficient nourishment. This has been realized with 
phosphorus in the case of the liver, and with cantharides in the case 
of the kidneys. 

Epithelial Origin of Sclerosis. — The preceding facts force us to 
admit that sclerosis is the cicatrix of cellular lesions, and lead us to 
reject the existence of primary scleroses. The consecutive tissue altera- 
tion is always preceded by a lesion bearing on the more highly organ- 
ized elements. Scleroses, therefore, are always of epithelial origin. 

For example, let us take an organ in which scleroses have fre- 
quently been studied — namely, the kidney. Two types of nephrites 
were formerly admitted, some epithelial, others interstitial — i. e., scle- 
rotic from the beginning. To each of these affections a different eti- 
ology, pathogenesis, and symptomatology were assigned. Little by lit- 
tle a change was wrought. It has finally become recognised that every 
nephritis starts with the epithelial elements, and that the process soon 
extends, so that nephritis is primarily diffuse and subsequently ad- 
vances toward different anatomical types, the two extremes of which 
are represented by the large white kidney, where epithelial lesions pre- 
dominate, and by the small, contracted red kidney in which sclerotic 
lesions prevail. Thus are produced sharply distinguished affections, 
which must be separated in anatomical and clinical descriptions. The 
starting point, however, is the same, but the final result differs because 
organisms are not similar. 

The same conception is applicable to hepatic cirrhoses. The origin 
must be looked for in a primary lesion of the hepatic or biliary cells. 
The still classical idea which attributes atrophic cirrhosis to a pri- 
mary alteration of the portal vein or to a periportal cirrhosis is based 
upon incomplete anatomical study. It is now demonstrated that the 
process is not as systematic as was formerly supposed. Sclerosis de- 



EVOLUTION OF INFLAMMATIONS— SCLEROSIS 301 

velops simultaneously around the portal and hepatic veins and forms 
aberrant bands, defying all topography. On the other hand, a scle- 
rotic lesion is never seen to radiate toward neighbouring parts. It 
is probable, then, that poisons and microbes carried by the portal vein 
give rise to primary alterations in the hepatic cells. The marginal 
cells are the first to be reached and the most profoundly affected. 
Next to be attacked are the centrally located cells in the region where 
the blood which has passed through the radiate capillaries enters the 
central vein. In this way the topography of sclerotic lesions is ex- 
plained. As to the venous alterations, they seem most frequently to 
be secondary. It may, however, be admitted that they are sometimes 
primary, in which instance they produce sclerosis because the dis- 
turbances of circulation alter the nutrition of the cells. Even in this 
case the sclerotic process is not an irradiation of the periphlebitis; 
on the contrary, it is consecutive to a degenerative alteration of the 
hepatic cells. 

When the question is one of biliary hypertrophic cirrhosis, there 
can then be no doubt as to the primary lesion being located in the cells. 
It affects the epithelia of the biliary passages and seems to be caused 
by the colon bacillus coming from the intestine. 

It would be easy to present analogous examples with respect to 
other glands and various tissues. Therefore, sclerosis always comes to 
fill up a vacant space. 

Scleroses of the nervous tissue form no exception, since it is now 
known that scleroses of the neuroglia do not enter into the group of 
true scleroses. The neuroglia does not represent connective tissue; 
it is of ectodermic origin and a nervous tissue. It is not strange, 
therefore, that it should be the seat of systematic lesions to which 
the rules here laid down do not apply. It is a special process quite 
different from true mesodermic sclerosis. 

Arteriosclerosis. — Instead of being localized at a certain point, as 
in the preceding examples, sclerosis may be generalized, or at least 
distributed to a great part of the organism, affecting especially the 
vascular system and attacking several viscera at once. 

It is to the history of this morbid state that the law which we have 
above formulated especially applies. Arteriosclerosis is truly the last 
stage of all morbid, infectious, or toxic causes which have acted during 
life. The reason why the arteries are so often affected at a relatively 
early age and at a time when the organs are still quite healthy is that 
they serve to carry microbes and toxines and are constantly contami- 
nated by noxious substances. The most highly organized elements of 
the vessel walls, notably the muscle fibres, degenerate and sclerosis is 
produced. 



302 INTRODUCTION TO THE STUDY OF MEDICINE 

Arteriosclerosis, which may commence at an early age, is almost 
never absent in the aged or even in adults. There are records of 
men whose arteries were supple at the age of eighty or ninety years. 
Such instances, however, are very rare. More frequently arterioscle- 
rosis is manifest as early as the thirtieth to the thirty-fifth year. Even 
when arteriosclerosis is extensive, it is not everywhere equally marked. 
The lesions predominate in the small arteries, where friction is more 
energetic, and near the angles, curves, and divisions, where the impact 
of the blood current is stronger. On the other hand, however, it seems 
that the process is essentially regional, and that the territories chiefly 
affected are those which correspond to the most active parts. Com- 
parative pathology has shown us that arteriosclerosis is frequent in 
animals. In the horse it is localized in the lower portion of the aorta 
— that is, in the vessel charged with the function of supplying blood to 
the most active muscles. 

Arteriosclerosis, while especially marked in the radial vessels of 
labourers, seems to affect the arteries of the head in men addicted to 
mental occupations, and quite often begins in the temporals. There 
are evidently many exceptions to these rules, which, however, appear to 
be sufficiently well established to warrant citation. 

An artery affected with sclerosis may be the seat of various disturb- 
ances. The disappearance of the muscular fibres from the walls of 
arteries lessens their resistance and often leads to dilatations, aneu- 
risms of calibre, or miliary aneurisms. The part thus affected may 
burst, as is frequently the case in miliary aneurisms. In other 
instances the blood coagulates in contact with the diseased vessel 
wall, particularly when the latter has suffered atheromatous or cal- 
careous degeneration. According to the diseased vessel, necrobiosis 
or gangrene will be produced. For example, in the brain a focus 
of softening will appear; and in the extremities, dry or senile 
gangrene. 

Simultaneously with the appearance of arteriosclerosis, analogous 
changes occur in the viscera. 

There has been much discussion as to the relations existing between 
arterial and visceral sclerosis. In this connection four principal the- 
ories have been advanced : Drs. Huchard and Weber assume the occur- 
rence of a periarteritis radiating from the affected artery toward the 
neighbouring tissues. Dr. Martin believes that a nutritive disorder 
due to deficient circulation exists. The most differentiated — i. e., the 
most delicate — parts are the first to degenerate and be replaced by 
fibrous tissue. Ziegler goes further, and states that there is an oblit- 
eration of the small vessels. According to this third hypothesis, scle- 
rosis would be a cicatrix of a necrosis of thrombotic origin. Finally, 



EVOLUTION OF INFLAMMATIONS— SCLEROSIS 303 

according to Brault and Mcolle, scleroses of arteries and viscera are 
dependent upon the same causes; they are simply of simultaneous 
origin. 

Evolution and Clinical Forms of Arteriosclerosis. — Clinically 
arteriosclerosis develops in such a manner that three stages may be 
admitted : 

In the first stage the arterial phenomena predominate. This is 
the case in individuals who have passed the age of forty. One of the 
first and the most important manifestations experienced by them is 
dizziness. The subjects complain of dyspnoea, which is sometimes of 
an asthmatic character, somnolence after meals, and hemicrania. It 
is well to mistrust so-called asthmas and hemicranias occurring in per- 
sons of a certain age. These manifestations nearly always point to an 
arteriosclerosis and often announce an alteration of the kidneys. At 
the same time, especially in women, there are observed vasomotor 
disturbances, sudden congestions and sensations of heat, which are 
only too often charged to the menopause. 

If these first phenomena be well interpreted, they lead to an exami- 
nation of the circulatory apparatus. On auscultation of the heart a 
tympanitic click is heard accompanying the second sound, and at times 
even systolic and diastolic murmurs, which, however, are transient and 
intermittent. The arteries are somewhat hard; the sphygmograph 
shows a flattening at the summit of the line of ascension. The sphyg- 
momanometer indicates an elevated pressure — 20 centimetres on an 
average. 

In the second stage the manifestations are localized — i. e., pre- 
dominate in a viscus. The disturbances, however, are transitory and 
intermittent, and are produced only on the occasion of excessive func- 
tional activity. Professor Grasset has felicitously compared these 
phenomena to the intermittent claudication (limping) observed in old 
horses affected with atheroma of the lower portion of the aorta, and 
which occurs only at times of somewhat hard work. The muscles, 
sufficiently nourished when they are at rest, do not receive blood 
enough to enable them to continue their activity; being deficiently 
supplied, they contract badly. The same manifestations may be 
observed in man, in whom an intermittent claudication of the limbs 
is noted; but, according to Grasset's expression, an intermittent clau- 
dication of the organs more frequently exists. Such are transitory 
paroxysms of asystole, cerebral clouding, and slight accidents of 
uraemia with a little albumin. 

The third stage is characterized by the localization of the process, 
or at least by its predominance in an organ. According to the part 
affected, four clinical types may be admitted : 



304 INTRODUCTION TO THE STUDY OF MEDICINE 

Arteriosclerosis of a cardiac type, in which the heart, invaded by 
sclerosis (sclerotic myocarditis), weakens progressively. The patient 
falls into a state of remarkable asystole, not as a result of the intensity 
of the symptoms, but owing to their persistence and the impossibility 
of a complete disappearance of the disturbances. 

Arteriosclerosis of an arterial type, characterized by the develop- 
ment of vascular dilatations, and particularly aneurisms. 

Arteriosclerosis of a cerebral type, starting with vertigo and hemi- 
crania and terminating in softening by obliteration of the diseased 
vessels, or in meningeal and cerebral hemorrhage resulting from rup- 
ture of a miliary aneurism. 

Arteriosclerosis of a renal type, anatomically characterized by an 
interstitial nephritis, and clinically by polyuria, slight and often tran- 
sitory albuminuria, cardiac palpitations, arterial overtension — going 
as high as 25 centimetres — and a galloping murmur. It ends in death 
by uraemia, asystole, and sometimes by pulmonary apoplexy. 

Therapeutics. — It is difficult to combat the development of scle- 
rosis. Only one medicine seems capable of arresting the advance of 
the process, and that is potassium iodide. In order to obtain good 
results, this drug must be prescribed in small and long-continued 
doses. It may be given in daily doses of 20 or 25 centigrammes for 
about three weeks, to be resumed after an interruption of ten days or 
so. It should be continued in this way for a year and more. Simul- 
taneously, the circulation may be facilitated by stimulating dilatation 
of the vessels. To this end, three medicines are useful — namely, so- 
dium iodide, trinitrine, and amyl nitrite. Sodium iodide acts slowly, 
and is to be given in doses of 1 gramme daily. The action of trini- 
trine is more marked and rapid. It is prescribed in doses of 1 or 
2 milligrammes. Amyl nitrite, on account of its instantaneous 
effects, best serves against such accidents as are to be combatted imme- 
diately. The inhalation of a few drops of it evaporated from a hand- 
kerchief may ward off the various paroxysms to which arteriosclerotic 
subjects are exposed, such as angina pectoris, vertigo, and asthmatic 
dyspnoea. 



CHAPTER XVII 
TUMOURS 

Division and classification of tumours — Embryogenetic and histogenetic tumours 
— Benign and malignant tumours — Typical and atypical tumours — Develop- 
ment of tumours — Consideration on the etiology — Relationships between in- 
flammation and tumours — Pathogenetic theories — Parasitic theory — Thera- 
peutics. 

Tumours constitute an artificial group whose already well-ad- 
vanced divisions will be continued and completed with the progress of 
science. In his justly celebrated treatise, Virchow described the 
lesions of tuberculosis, glanders, and syphilis along with tumours. 
To-day these are held by all to be of infectious origin. For a long 
time actinomycosis was looked upon as sarcoma, and, in fact, the 
microscope revealed in actinomycotic lesions a structure justifying 
this conception. The discovery of the pathogenic agent, however, has 
brought the question to its proper position. Likewise, the various 
sarcomatoid lesions have been referred to tuberculosis as the result of 
bacteriological researches. In the dog, for example, Koch's bacillus 
gives rise to lesions of a neoplastic character, which had long been 
considered as malignant tumours. 

Even quite highly organized parasites may give rise to the devel- 
opment of tumours. With Cadiot and Gilbert, we have observed in a 
female dog vaginal polypi due to the presence of acarus. Albarran 
and Bernard had the opportunity of studying a tumour of the bladder 
which possessed all the characters of epithelioma, but which, in reality, 
was due to the eggs of Bilharzia hcematobia. 

A whole series of lesions of parasitic origin may at present be 
separated from the group of tumours ; the remainder comprise produc- 
tions the nature of which is absolutely unknown, but which, according 
to perfectly acceptable theories, seem to be referable to animate agents. 

Division and Classification of Tumours. — The insufficiency of path- 
ogenic data compels us to retain the old division of tumours into 
benign and malignant. This division is justified from both a clinical 
and pathologico-anatomical standpoint. 

305 



306 INTRODUCTION TO THE STUDY OF MEDICINE 

Benign tumours may be considered as hyperplasias of inflamma- 
tory origin; such are best exemplified by the keloid, an exuberant 
fibrous production developing in cicatrices. Histological examination 
demonstrates that benign tumours are made up of tissues having a 
normal arrangement, or at least preserving some of the characters 
recalling their origin. When adenoma is studied, it is found to have 
a glandular structure. The cells have proliferated and filled the alve- 
oli, but they have preserved their general arrangement; they remain 
inclosed by the limiting membrane, and manifest no tendency to invade 
the surrounding tissues. 

In malignant tumours, on the other hand, the disorder is absolute. 
The cells, which are of varied form and fantastic in aspect, are inclosed 
in alveoli of new formation; they penetrate the limiting membrane 
and invade the neighbouring tissues. Malignancy, therefore, is char- 
acterized histologically by irregularity of form and structure.. Ac- 
cording to the felicitous expression of Dr. Bard, the process is one of 
cellular anarchy. 

Embryological Tumours. — A group of productions sufficiently well 
defined is usually classed with the tumours. We refer to those which 
are due to defects of development — i. e., to embryogenetic disorders. 
We shall divide them into four groups : The first and second com- 
prise those tumours starting during the embryonal or foetal period of 
a being; the third and fourth consist in post-natal morbid processes 
occurring in the reproductive organs. 

Of the embryological tumours, we may first cite the parasitic 
grafts. In studying teratology, we have seen that two spermatozoa, 
penetrating into one ovule, give birth to two beings, which develop 
side by side. In many cases, one of the two develops in a normal 
manner, whereas the other remains rudimentary and constitutes a 
more or less deformed mass, which may become inclosed in its well- 
constituted fellow, and thus form a tumour. Critzmann has at- 
tempted to generalize this process and offer it as an explication of the 
development of all neoplasms. 

A second group is represented by defects of development, of which 
three types may be admitted. 

Under the influence of unknown causes, a bud springing from 
certain parts will become inclosed in neighbouring or subjacent parts. 
This process is observed especially in branchial clefts, where the ecto- 
dermic and endodermic layers come into contact. An irregular union 
of the clefts explains the development of dermoid cysts of the neck. 
This is also an instance of particular evolution, which Cohnheim has 
attempted to generalize, by assuming that all tumours can be explained 
by the theory of inclusion. 



TUMOURS 307 

To the second variety belong cases of heterotopy. An aberrant 
lobe of an organ may produce a tumour by anomalous development. 
For example, accessory suprarenal capsules may penetrate into the 
kidney, vegetate there, and give rise to neoplasms. 

Lastly, in some cases transitory organs, such as the Wolffian duct 
and Mullens canal, persist, at least in a part of their extent, and thus 
give rise to a tumour. 

All the productions which we have thus far studied were connected 
with the development of the being; those of which we are presently to 
speak are dependent upon anomalies of fecundation. 

It is admitted that in certain instances tumours take their origin 
in the sexual glands. Facts of this kind are observed chiefly in the 
ovaries. Two theories are presented: one assumes an ovular fecunda- 
tion, the other parthenogenesis. 

According to the advocates of the first doctrine, a spermatozoon 
makes its way into the Fallopian tube, arrives at the ovary, and 
fecundates an ovule which enters upon segmentation. As it does not 
there find conditions favourable for its development, it gives birth to 
a monstrosity which constitutes a variety of dermoid cyst. Opposed 
to this theory is that of parthenogenesis. An ovule, stimulated perhaps 
by a normal concomitant or preceding fecundation, makes an abortive 
attempt at segmentation, which results in the production of a tumour. 
Although dermoid cysts are in most cases congenital tumours to be 
explained by inclusion, there are instances in which they seem to be 
developed after birth. In certain cases where the integrity of the 
ovary had been proved during a laparotomy, subsequent intervention 
has been necessitated by a dermoid cyst which did not exist at the 
time of the first intervention. Lastly, there remain two types of 
tumours dependent upon an incomplete development of the being. 
These tumours are observed in the uterus. One of them, known as 
mole, is produced by a myxomatous degeneration of the foetal meso- 
derm. This is an innocent lesion, curable by means of simple curet- 
tage. The other behaves as a malignant tumour. This is known as 
deciduoma, which develops at the expense of the placental epithelium 
and of the foetal ectoderm. 

Histogenetic Tumours. — Those tumours not of embryonic origin, 
and which, in contradistinction from the latter, we call histogenetic, 
may be divided into four groups, according as they develop from con- 
nective, muscular, nervous, or epithelial tissue. 

In each group there are to be admitted a certain number of vari- 
eties, which are very easily remembered, as each of them corresponds to 
a normal tissue. 

The tumours of the connective group may be of an embryonic 



308 INTRODUCTION TO THE STUDY OF MEDICINE 

nature. These are the sarcomata, which are remarkable for their tend- 
ency to extend. Clinicians have considered them as transitional be- 
tween the benign and cancerous tumours. They are tumours with a 
variable prognosis. 

The other connective-tissue varieties give origin to tumours whose 
tendency to spread will be the weaker the less vitality the tissue pos- 
sesses in its normal condition. Myxoma corresponds to mucous tissue, 
fibroma to fibrous, and lipoma to adipose tissue. 

The derivatives of connective tissue — i. e., cartilage and bone — give 
origin to chondroma and osteoma. 

Vascular tissue belongs to the same blastodermic layer. We may 
therefore include under the same group the sanguineous and lymphatic 
angiomata and endotheliomata produced at the expense of serous mem- 
branes, representing derivatives of the lymphatic system. Lymphoma 
may also be included here. 

Muscular tissue gives origin to but two species of tumours. These 
are leiomyomata and rhabdomyomata, which correspond to the non- 
striated and the striated muscle fibres respectively. 

Two types of tumours may also take origin from nervous tissue — 
namely, neuroma and glioma. The latter has often been considered 
as sarcoma. This, however, is an error due to a false idea which, up 
to a recent date, prevailed in regard to the blastodermic origin of neu- 
roglia. At the time when the neuroglia was held to be the connective 
tissue of the nervous centres — that is, a mesodermic production — the 
comparison was acceptable. At the present time, however, it is known 
that the neuroglia is an ectodermic production. Glioma, therefore, is a 
tumour claiming its proper place. 

The most interesting facts are found in connection with tumours 
of epithelial origin. Passing by the papillomata, which are small 
tumours of little importance, due to an excessive development of the 
papillas of the skin and mucous membranes, and which might just as 
well be classed among tumours of connective-tissue origin, we come to 
the consideration of the two great categories of adenomata and epi- 
theliomata. Between the two we shall place cysts, which may be 
classed with one or the other group, as the case may be. 

Such, in its entirety, is the classification of tumours, according to 
the most recent investigations and the data obtained from embryology 
and histology. 

In order to facilitate recollection of the different types which we 
have here admitted, we give the following tabulated representation 
summarizing the general notions above referred to : 



TUMOURS 309 



TUMOURS. 

Embryogenetic. 

Beginning during intrauterine life. 

Parasitic grafts. 

Inclusion. 

Heterotopy. 



Defects of development. . 



Persistence of a transitory part. 
Developing during the genital period. 

Acquired dermoid cysts. (Parthenogenesis ?) 

( Mole. 

Intrauterine tumours \ -n . -, 

I Deciduoma. 

Histogenetic. 

Of connectivo-vascular origin. 

Sarcoma. 

Myxoma. 

Fibroma. 

Lipoma. 

Chondroma. 

Osteoma. 

Hemangioma. 

Lymphangioma. 

Endothelioma. 

Lymphoma. 

Of muscular origin. 

Leiomyoma. 
Rhabdomyoma. 

Of nervous origin. 

Neuroma. 
Glioma. 

Of epithelial origin. 

Papilloma. 
Adenoma. j 
Epithelioma. } Cysts ' 

Between adenoma, a benign tumour, and epithelioma (a malignant 
tumour which corresponds to what is clinically called cancer) there exist 
numerous transitions. The typical cases, however, differ considerably. 
In order to comprehend the distinction, let us consider any gland. We 
find canals limited by a membrane which is lined with an epithelial 
layer. In adenomata the epithelium proliferates and new glandular 
alveoli appear. Sometimes the excretory orifice becomes obliterated 
and the glandular cavity is transformed into a cyst. However, be the 
evolution what it may, we always find the enveloping membrane as 
well as the epithelium with its fundamental and typical characters. 

In epithelioma, cellular proliferation is not necessarily more promi- 
nent than in adenoma. Indeed, at times this phenomenon is even 



310 INTRODUCTION TO THE STUDY OF MEDICINE 

less active. The characteristic feature of a malignant tumour lies in 
the disposition of the cells to penetrate or break through the basement 
membrane and invade the surrounding parts, behaving as true parasites. 

In studying certain tumours, all the transitions between adenoma- 
tous formation and epitheliomatous degeneration may be followed. 
In the mamma, histological sections are often highly demonstrative. 
At certain points the process is still circumscribed and clearly intra- 
canalicular ; in others, on the other hand, invasion has taken place and 
the tumour has assumed an epitheliomatous appearance. 

The former classical distinction between epithelioma and carcino- 
ma is no longer admitted. Carcinoma was at one time considered to 
be a tumour of connective-tissue origin, but at the present time its epi- 
thelial nature is no longer a matter of doubt. Carcinoma, therefore, 
is an epithelioma the cells of which are inclosed in a very plentiful 
stroma. According to the development of the interstices, the neoplasm 
is soft or hard. In the former instance it is designated as mccphaloid, 
and in the latter as scirrhus. When the elastic fibres become abundant 
in the interstitial tissue, the volume of the tumour may be reduced by 
their retraction. This is known as atrophic scirrhus. 

Since the studies of Malassez, epitheliomata are divided into typi- 
cal, metatypical, and atypical. This division is an excellent one and 
may be applied to all tumours. 

Typical tumours present a structure recalling that of the tissue 
from which they develop. Thus, in the intestine, where cylindrical epi- 
thelium exists, the tumour will be an epithelioma with cylindrical 
cells; in the skin and buccal cavity it will be a pavement-celled epi- 
thelioma; and in the liver, a trabecular epithelioma. 

When the tumour is composed of a tissue having its analogue in 
some portion of the economy, but not occurring at the affected point, 
the term metatypical is applied to it. Thus, for example, chon- 
dromata are met with in the testicle or the parotid gland, and epi- 
theliomata in the maxillae. These facts, which at first sight are so 
astonishing, find an explanation in embryology. The cartilaginous 
tumours of the parotid are due to the persistence of remains of 
Meckel's cartilage; those of the testicles are due to the fact that this 
gland was at first located in front of the vertebral column, and that 
at that time some cartilaginous cells of the neighbourhood were in- 
closed in it. Similarly, epitheliomata of the maxillary bone originate 
from paradental epithelial remains. 

Atypical tumours are those in which cellular evolution has com- 
pletely deviated from the normal type and in which the cells often as- 
sume forms and arrangements which are without analogy in the or- 
ganism. 



TUMOURS 311 

Neoplasms may be seated in any part of the organism, but they are 
particularly frequent in localities where several types of tissue unite — 
a fact which has been made use of by advocates of the inclusion 
theory, according to which ectopy of one tissue toward another exists. 

Development of Tumours. — Tumours develop according to the 
same mechanism as normal tissues. The differences that have been 
noted are of but secondary importance. Thus, for example, anomalous 
karyokinetic figures are often found in epitheliomata. Instead of two 
amphiasters, there may be three, four, and even five; the nuclei are 
irregular; the cells are incompletely divided, and may acquire a co- 
lossal volume. 

Too much importance, however, should not be attached to these 
facts, since analogous phenomena are observed whenever proliferations 
are very active, as, for example, under the influence of chemical irrita- 
tions. The glycogenic infiltration of cells must also be referred to 
activity of development. In all proliferating tissues, in the embryo as 
well as in the adult, great quantities of glycogen are found. 

The activity of proliferation and the insufficiency of blood supply 
explain the frequency of cellular degeneration. Sometimes the cells 
undergo fatty degeneration, sometimes colloid degeneration, the latter 
being particularly frequent in the thyroid gland, stomach, and intes- 
tines; sometimes mucous degeneration, horny transformation, and 
pigmentary (melanotic tumours) or calcareous infiltration occur. In 
other cases the central cells become necrotic and the tumour is trans- 
formed into a cyst. 

Etiology. — Tumours may be observed at all ages, but their fre- 
quency and nature vary considerably at different periods of life. In 
the embryo tumours are dependent upon defects of development. The 
most frequent are angiomata, though some exceptional cases of con- 
genital epitheliomata have been noted. 

During early infancy sarcomata are observed, located chiefly in 
the kidneys. At puberty, exostoses are frequent. In women, at a 
later period, ovarian cysts belonging to the group of adenomata and 
epitheliomata are encountered. From the age of fourteen onward 
epithelioma becomes more and more common, reaching its maximum 
of frequency between the age of fifty and fifty-five years. 

Age exercises no less influence upon the localization than upon the 
nature of tumours. In children they affect, in order of frequency, the 
eye, where melanotic sarcoma is met with, the kidney, testicles, 
spleen, and more rarely the other organs. In adults the portion of 
the body most frequently attacked is the stomach; then come the 
uterus,* the liver, the mamma, and the intestine, in the order named. 

* In America, according to Welch's statistics, the uterus stands first. 
21 



312 INTRODUCTION TO THE STUDY OF MEDICINE 

Among causes explaining the development of tumours, heredity 
stands first. Some authorities have admitted indirect heredity as 
well as direct heredity, which, according to Delbet's statistics, is ob- 
served in from 10 to 15 per cent of the cases, according to the theory 
of indirect heredity. Cancer is mainly observed in families of arthrit- 
ics, and this accounts for its frequency in civilized races. The great 
number of cases occurring in certain regions, local epidemics, and the 
influence of water are interesting questions which are still sub judice. 
The same statement may be made in regard to alimentation, certain 
authorities claiming that meat, and others that vegetables, exercise an 
influence in etiology. 

The development of a tumour is often referred by the patient to 
a previous traumatism. In spite of undoubted exaggeration, facts of 
this kind are too frequent to be ignored. It is certain that contusions 
have been the starting point of caseous sarcomata and of testicular or 
mammary tumours. Tumours are, perhaps, more frequently due to 
friction or repeated irritation. The cancer of the testicle and scrotum 
observed in chimney sweepers, and epithelioma of the lip in smokers, 
come under this group. It is well known, however, that the so-called 
smokers' cancer is also observed in individuals who have never made 
use of tobacco. 

Cancer has also been seen to develop at the seat of old cautery 
wounds and in ectopic testes. 

In certain cases chemical and not mechanical irritations inter- 
vene. According to Hoerting and Hesse, men employed in arsenical 
cobalt mines are often attacked with pulmonary sarcoma. 

Old affections of long duration keep up a chronic irritation, which 
is equally apt to favour the development of tumours. Old cutaneous 
lesions, such as psoriasis, lupus, and extensive cicatrices, especially 
those consecutive to burns, have been seen to undergo epitheliomatous 
transformation. The same phenomenon has been observed in mu- 
cous membranes. For example, buccal psoriasis may degenerate into 
epithelioma; and similar transformations occur in the vagina and 
uterus. 

In other instances cancer is developed at the seat of a lesion kept 
up by a foreign body. Whether the latter be of external origin or is 
formed within the organism, the result is the same. In the mouth, 
for example, a carious tooth will keep up a lingual ulceration, which, 
although at first simple, may subsequently become cancerous. In the 
stomach the exciting agent may be a foreign body which has acci- 
dentally been swallowed ; and in the biliary passage hepatic calculi may 
be the causative agents — a fact which explains the greater frequency 
of cancer in the biliary passages of women, who are more often 



TUMOURS 313 

affected with lithiasis, whereas in men cancer of the liver is mainly 
encountered. 

Finally, lesions which were for a number of years dependent sim- 
ply upon a chronic inflammation may, at a given moment, terminate 
in cancer. Between simple inflammations and epitheliomata there are 
innumerable transitions. We have already shown the frequency of 
hyperplastic processes in all inflammations. When the stomach is 
affected, as is most frequently the case, glandular alveoli develop, 
undergo adenomatous transformation, and the adenoma is subse- 
quently transformed into cancer. This process is clearly observed in 
chronic gastritis, and still more clearly in cases of gastric ulcer. 

Examples of the same order may be presented in connection with 
other parts of the organism. In the intestine, for example, the phe- 
nomena are developed in the same manner as in the stomach; in the 
liver and kidneys epitheliomatous tumours, improperly called adenom- 
ata, have often been seen to ingraft themselves upon a cirrhosis or 
an interstitial nephritis. 

Pathogenesis. — In order to explain the development of tumours, 
and especially of cancer, many hypotheses have been advanced. By 
generalizing from a particular case, Cohnheim maintained that neo- 
plasms are due to inclusions occurring during the embryonal period, 
the masses of nonemployed cells developing at a later date, as a result 
of a lack of resistance on the part of neighbouring tissues. A good 
many objections may be raised in opposition to this theory. First, it 
necessitates two hypotheses — namely, on the one hand, inclusion, and, 
on the other, feebleness of parts surrounding the invaginated ele- 
ments. By admitting the reality of these two conditions, it is not 
readily understood why the cells remain inactive for years to become 
active at the moment of involution. Nor is it comprehensible why 
traumatism, organic lesions, and chronic inflammations serve as a 
starting point for the tumour. It would be necessary to maintain 
that foetal inclusion has occurred precisely at that point. Finally, 
tumours which we know to be of embryonic origin — e. g., dermoid 
cysts — behave quite differently, and the cells contained in them are 
of adult type, advanced in development, and not active cells, as are 
those in neoplasms. 

The same remarks are applicable to the views of Bard, who as- 
sumes the occurrence of monstrosity in the cellular development, and 
who thinks that the mutual induction exercised by the various cells 
upon each other is broken. It is evident that the reality of these 
various hypotheses should first be demonstrated. 

In contrast to the theories of Cohnheim and Bard, who assume a 
disturbance of development in tissues, and dropping out of considera- 



314 INTRODUCTION TO THE STUDY OF MEDICINE 

tion the theory of Rindfleisch, who explains the development of 
tumours by the absence of nerves, we find a more modern conception 
which, far from seeking the cause of the phenomena in an internal 
deviation, places it outside of the organism. This is the parasitic 
theory of cancer. 

In favour of this theory, it may be remarked that a great number 
of lesions formerly considered as tumours are to-day classed with the 
group of parasitic affections. Without referring to tubercle, it will 
suffice to mention actinomycosis. 

A second argument is drawn from the evolution of cancer. The 
cancerous cell behaves as a parasite; the lesions have an invading 
march and may spread in the manner of grafts. An epithelioma may 
propagate by contiguity from one lip to the other, and from the stom- 
ach to the liver or pancreas ; it may invade the lymphatics or extend 
from one viscus to another through the process of embolism; it may 
become generalized and give rise to miliary carcinosis, the evolution 
of which recalls that of acute tuberculosis. 

There are on record certain facts which tend to prove even the 
inoculability of cancer, and in regard to subjects suffering from cancer 
the fact is unquestionable. The transmission of cancer from diseased 
to healthy man is, however, less well established, notwithstanding a 
few observations in which cancer of the penis has been observed in 
men whose wives were affected with carcinoma of the uterus. Experi- 
mental pathology does not confirm this result. Attempts to inocu- 
late human cancer into animals, or from one animal to another of a 
similar species, have thus far been wholly unsuccessful. The only 
positive results have been observed by Hanau and Moreau in rats and 
mice. According to Menetrier, inoculation is not successful unless 
practised upon animals of the same family, in which cancer has al- 
ready appeared, and subsequently manifests itself in several indi- 
viduals of that family. This is, as it were, making the inoculation 
upon the subject himself. In regard to innocent tumours, the trans- 
missibility of warts and vegetations occurring upon the genitals of 
man and animals is well established. 

The parasitic nature of tumours is not supported by sufficient 
proofs to warrant acceptance of this theory. The question is simply 
one of persuasion. To change the theory into a certainty, it is evi- 
dently necessary to discover the pathogenic agent, and attempts thus 
far made have resulted negatively. 

The microbes described by Eappin and Scheurlen in 1883 and 1887 
respectively have quickly passed into oblivion. It may be asked 
whether the coccidia observed by Thomas and studied in the vege- 
tating follicular psorospermosis by Darier, Malassez, Albarran, Foa, 



TUMOURS 315 

and Buffer are actually the cause of tumours. In reply to this ques- 
tion, it may be stated that the preparations and drawings furnished by 
these authors have not offered convincing evidence. On the contrary, 
many histologists maintain that the figures given as examples of 
intracellular coccidia are in reality dependent upon degenerations 
occurring in the cancerous cells. The discussion will last as long as 
the parasite eludes cultivation. 

Since the contributions of Busse, San Felice, and Maffucci, atten- 
tion has been directed to the blastomycetes. Yeasts have several 
times been found in tumours. Curtis was able to isolate and cultivate 
a species and also to produce tumours in animals by inoculation. 
Here, then, is another neoplastic production which passes into the 
group of parasitic lesions. 

It is probable, if not certain, that division will continue, and that 
in the near future all tumours will be considered as due to animate 
agents. This, however, is only a hypothesis which is supported by a 
small number of facts. 

Furthermore, what convinces us that the parasitic conception must 
be real is the fact that tumours not only propagate and become gen- 
eralized, as do infectious lesions, but they produce in the entire organ- 
ism modifications which can hardly be explained in the absence of this 
hypothesis. The rapid emaciation, special cachexia, visceral lesions, 
nutritive disturbances, and notably the diminution of urea (Romme- 
laere), seem to demonstrate the intervention of a parasitic cause. 
We are even naturally led to ask whether intoxication by products 
engendered in the tumour may not play an important role. Notwith- 
standing some positive results, it must be acknowledged that the 
majority of experimenters have failed to discover any toxic substance 
in the tissues of neoplasms. 

Whatever theoretical idea may be adopted, discussion is useless. 
Neoplasms must be treated as parasitic lesions; they must be extir- 
pated, and that, too, as soon as possible. Internal medication is 
absolutely valueless; there are no specifics or antiseptics which will 
oppose them. Interstitial injections, except possibly those of arsenic, 
have met with no better success. However, it has been observed that 
neoplasms, notably sarcomata, were apt to subside under the influence 
of an intercurrent erysipelas. Coley conceived the idea of turning 
this result to account in therapeutics. His method, which consists in 
injecting a mixture of sterilized cultures of streptococcus and Bacillus 
prodigiosus, seems to have met with some success, at least in the case 
of sarcomata. The procedure has been modified by Schoull, who 
employs the serum of animals infected with streptococcus. The re- 
sults have been too discordant to lead to any definite opinion. The 



316 INTRODUCTION TO THE STUDY OF MEDICINE 

same remark may be made concerning the method of Eichet and 
Hericourt, who prepare a serum by injecting cancerous juice into 
animals. 

In brief, all these attempts, however interesting they may be, have 
as yet yielded no practical results. An early and radical extirpation 
of the affected part and corresponding ganglia must be resorted to, 
and it is well to remember that, in spite of all precautions, recur- 
rence too often supervenes at the end of a certain time. 



CHAPTER XVIII 
CELLULAR DEGENERATIONS 

Various forms of cellular degenerations — Cloudy swelling — Granulo-albuminous 
and granulo-fatty degenerations — Mucoid degeneration — Hyaline and amyloid 
degenerations — Glassy degeneration and coagulation necrosis — Caseous degen- 
eration — Pigmentary degeneration — General etiology and pathogenesis of de- 
generations — Special study of fatty, amyloid, and pigmentary degenerations. 

Division and Classification. — We have repeatedly pointed out the 
degenerations which occnr in cells. In treating of inflammation and 
in describing tnmonrs we show the frequency of alterations of cellular 
protoplasm. 

The first stage of cellular degeneration is marked by the occur- 
rence of cloudy swelling. The cells are swollen and filled with an 
albuminous or serous fluid holding small granules in suspension. The 
latter occur in two forms, namely, in granulo-albuminous degenera- 
tion, which is the first stage, and in granulo-fatty degeneration, which 
is the second stage. In the former instance acetic acid swells the 
granules and then dissolves them; in the latter the granules are col- 
oured dark by osmic acid. This morbid state is observed in a great 
number of inflammations; it affects the protoplasm and may attack 
the nucleus and nucleolus. 

At a more advanced stage we find fatty degeneration, properly 
so called, or steatosis. This process, which plays a considerable part 
in pathology, must not be confounded with fatty infiltration, which, 
for instance, is observed in obesity. In fatty infiltration there is 
simple deposition of fat in the interior of the cell ; the protoplasm may 
be pushed aside, but its activity is hardly disturbed. In steatosis or 
fatty degeneration, on the other hand, the protoplasm itself is trans- 
formed into fat. Under the influence of nutritive disorders, the pro- 
teid matter undergoes a special metamorphosis ; therefore the physio- 
logical activity of the element is also profoundly affected, weakened, 
or even completely lost. 

Mucoid or colloid degeneration is observed in the epithelial cells. 
It is characterized by the deposition of mucinoid substance in the 

317 



318 INTRODUCTION TO THE STUDY OF MEDICINE 

interior of the protoplasm. This may be compared with vacuolar de- 
generation, in which vacuoles appear to be present in the cell. This 
phenomenon is in reality due to the presence of small cysts filled with 
an albuminoid matter. In colloid degeneration the material elabo- 
rated in the diseased cell may be expelled. If it enters an excretory 
duct it will be eliminated from the organism. Such, for example, is 
what takes place in the kidney: the colloid masses exuded from the 
cells into the lumina of the tubules unite to form cylinders, or so- 
called casts, which are revealed in the urine on microscopical exami- 
nation. When the substance is retained at the point of elaboration, 
it gives rise to the development of more or less voluminous cysts. 
Thus are explained the cystic degenerations of the kidney and liver, 
the formation of colloid cysts in the thyroid gland, etc. The same 
process, however, may also affect the pathological cells — cysts may be 
produced in tumours. The ovarian cyst, for example, is looked upon 
as an adenoma or epithelioma accompanied by colloid degeneration. 

Another important variety of degeneration is represented by hya- 
line degeneration. It is essentially characterized by the production 
of refractive homogeneous masses. It is frequently observed in cer- 
tain forms of nephritis, in inflammation of the ovary, and in tubercu- 
losis; and it is not rare in the small aneurisms which are found in 
the walls of tubercular cavities. According to Armanni, hyaline 
degeneration is frequently observed in the tubes of Henle in diabetic 
kidneys. The alteration found here, however, should be carefully dis- 
tinguished from hyaline degeneration, for, as Ehrlich has shown, it is 
really due to an infiltration of the cells by glycogen. 

Parallel with hyaline degeneration may be placed transparent 
degeneration, observed by Hanot and Gilbert in the livers of persons 
dead of cholera. In this condition the protoplasm of the hepatic 
cells becomes completely transparent, the nucleus alone persisting. 

Finally, Zenker's waxy degeneration is generally considered to 
be the same as hyaline degeneration. It is an alteration attacking 
the striated muscles. It was first encountered in the myocardium in 
typhoid fever, and was subsequently observed in a great number of 
infections ; it may also be experimentally produced by tetanization of 
the muscles. It is essentially characterized by swelling, hyaline meta- 
morphosis, and fragmentation of the muscular tissue. 

There is nothing precisely known concerning the nature of hyaline 
degeneration. It has been found that the substance which infiltrates 
the cells resists reagents. This fact has caused it to be compared to 
another variety of degeneration, which we shall study in a special 
manner — namely, amyloid degeneration. 

Hyaline degeneration must not be confounded with glassy degen- 



CELLULAR DEGENERATIONS 319 

eration. The latter is essentially characterized by a transformation 
of the cell, all parts of which lose their histochemical properties. The 
protoplasm, nucleus, and nucleolus are no longer differentiated. It 
would seem, therefore, that this process should be identified with the 
one already described in the section on inflammation under the terms 
fibrinoid degeneration or coagulation necrosis. As we have already 
stated, this is a process similar to the one presiding over the coagula- 
tion of organic substances containing fibrine. 

It is often stated that glassy degeneration is the first stage of 
caseation. In fact, it seems certain that the cells are first attacked by 
coagulation necrosis before undergoing the transformation or, one 
might almost say, the special fermentation which ends in their caseous 
degeneration. This process, which is mainly observed 'in tuberculosis 
and syphilis, has already been described in connection with the histo- 
genesis of tubercle. 

There still remains pigmentary degeneration, which is character- 
ized by a transformation of the protoplasm. It should not be con- 
founded with pigmentary infiltration, which is due to a simple accu- 
mulation of pigments transported to the cell. The difference here is 
the same as that between fatty degeneration and fatty infiltration. 

A sclerotic degeneration also is often spoken of. This is the process 
which we have already described as a mode of repair, a veritable cica- 
trization. Connective tissue develops in order to replace cells that 
have degenerated or disappeared. The cicatrized tissue is sometimes 
infiltrated with calcareous salts. This process is known as calcareous 
degeneration. 

Causes of Cellular Degenerations. — Although degenerations differ 
in their anatomical and clinical expression, and occur under condi- 
tions peculiar to each of them, and also have a dissimilar significance 
and evolution, the numerous varieties just described are, neverthe- 
less, united by analogous etiological and pathogenic conditions. 

Cellular degenerations always give expression to some nutritive 
disturbance. The latter may depend upon three distinct causes : (a) 
Deficient supply of materials destined for nutrition; (b) vitiation of 
the interstitial plasma — namely, an intoxication disturbing nutritive 
metabolism; and (c) disturbance or suppression of the functions of 
the cell. 

Thus viewed, it is easy to conceive the etiological conditions. 

At the head of the first group is naturally placed starvation. 
Now, it has been demonstrated by a great number of observations and 
experiments that suppression of alimentation is quite speedily fol- 
lowed by cellular degeneration. The form of degeneration produced 
under such circumstances is fatty metamorphosis. 



320 INTRODUCTION TO THE STUDY OF MEDICINE 

The same effects are observed when the blood is altered, either 
because it no longer brings to the cells a sufficient amount of aliment, 
or because it is not charged with a requisite amount of oxygen. The 
former condition is realized when the blood mass is lessened — for 
example, as the result of great hemorrhages; the latter occurs 
when the blood corpuscles are altered or decreased in number, as in 
anaemia. At all events, the cells soon undergo fatty degeneration, the 
frequency and extent of the lesions varying, however, according to 
the type of anaemia. While steatosis is exceptional in cases of chlo- 
rosis, it is constant in pernicious anaemia. 

General disturbances are not the only active factors ; local anaemias 
play a part which is by no means unimportant. Arterial strictures 
and obliterations cause degeneration of those parts insufficiently sup- 
plied with blood. 

It is stated that accumulation of carbonic acid in the tissues pro- 
duces the same effect as an insufficient supply of oxygen, and this 
explains the occurrence of degeneration in cases of venous oblitera- 
tion or cardio-pulmonary insufficiency. In this case, however, the 
process is rather one of intoxication, and we are thus led to our second 
group. 

It may be well to consider successively the role of exogenous and 
autogenous poisons. 

A very great number of mineral poisons give rise to cellular 
degenerations. It will suffice to mention arsenic, and especially phos- 
phorus. The latter substance produces diffused steatosis of all 
the anatomical elements, its action being particularly marked in the 
liver, which, in grave cases, undergoes complete degeneration. It 
is also by the production of cellular degenerations that other sub- 
stances give rise to cirrhoses. Sclerotic tissue makes its appearance 
to fill the vacancy created by the death of the more highly organized 
elements. 

The degenerations and scleroses consecutive to endogenous intoxi- 
cations are explained by the same mechanism. Whether the question 
be one of noxious products developed under the influence of cellular 
life or one of substances formed by bacteria normally or accidentally 
inhabiting our bodies, the result is the same. Let us assume, for ex- 
ample, that a calculus obstructs the exit of the bile. This secretion 
will excite a degeneration of the hepatic cells, and, passing into the 
circulation, will alter distant organs, particularly the kidney, in which 
it will give rise to a granulo-fatty degeneration of the epithelia. Let 
us now consider an exaggeration of gastrointestinal putrefaction. 
LTnder such circumstances a degeneration of the hepatic and renal 
cells will frequently be observed as the result of the absorption of the 



CELLULAR DEGENERATIONS 321 

excessive amount of toxines formed. As a dyspeptic liver exists, there 
is reason for describing a dyspeptic kidney. A good many cases of 
Bright's disease are referable to no other causation. Finally, we 
hardly need recall the fact that infection means intoxication, and that 
the soluble substances generated by the microbes produce numerous 
cellular degenerations. This result has been demonstrated by a large 
series of clinical observations and experiments. There is no subject 
which has been better studied. It is in the course of infectious diseases 
that the numerous varieties of degeneration above described are met 
with — namely, from cloudy swelling to steatosis, coagulation necrosis, 
and amyloid degeneration. 

We have stated that degeneration may be due to a suppression or 
disturbance of cellular activity. We must here introduce an impor- 
tant distinction. In cases of simple lack of function degeneration 
occurs, and not atrophy. The muscles of an individual who remains 
inactive diminish simply in volume; when a limb is placed in an 
immovable apparatus, it atrophies but does not degenerate. The same 
is true of glands which remain at rest. On the other hand, degenera- 
tion is produced when lack of activity results from functional dis- 
turbance. If, for example, a muscle or a gland remains at rest be- 
cause its nutrient vessels are altered, or because the nervous cells 
commanding the functions or the nerves transmitting the impulses 
are affected, it is not atrophy, but degeneration that occurs. Thus, 
section of a nerve does not act upon the muscle through the immobil- 
ity which it causes; on the contrary, the phenomena are more com- 
plex; there is a suppression of the necessary stimulus, and degenera- 
tion seems again to be connected with a trophic disorder. 

Without wishing to even briefly study the different varieties of 
degenerations, it may be well to give some complementary informa- 
tion concerning those most often met with and which have thus far 
only been alluded to — i. e., fatty degeneration and amyloid degenera- 
tion. We will then present some considerations relative to pigmen- 
tary degeneration. 

Fatty Degeneration. — Fatty degeneration or steatosis is essentially 
characterized by a fatty transformation of the nitrogenous matter 
which enters into the constitution of anatomical elements. As already 
stated, it should be carefully distinguished from fatty infiltration, 
which is in reality cellular obesity. A provision of fat is made in the 
cellular membrane, and, in order to make room for it, the protoplasm 
is slightly pushed aside. There is an addition of a new substance, and 
not metamorphosis of one already existing. From this point of view, 
the analyses of Perls are highly demonstrative. In fatty infiltration, 
the water contained in the tissues disappears and gives place to the fat ; 



322 INTRODUCTION TO THE STUDY OF MEDICINE 

in fatty degeneration, on the other hand, the albuminoid constituent 
yields its place to the fat element. 

Fatty degeneration may be established at once or follow another 
variety, such as granular degeneration, cloudy swelling, or albuminous 
infiltration. Under the microscope, in specimens fixed by means of 
osmic acid, fat appears in the form of small black coloured granules, 
isolated or united in masses, and particularly abundant around the 
nucleus. This steatosis is frequent in the liver, kidney, myocardium, 
and muscles. It originates under the most varied conditions. Nutri- 
tive disturbances produced by high temperatures are considered im- 
portant causative factors. The frequency of steatosis in infections is 
thus explained. It is well to note, however, that in this instance the 
problem is a very complicated one, since the alterations may more eas- 
ily be accounted for by a production of toxines than by thermal eleva- 
tion. Nevertheless, the intervention of the latter pathogenic condi- 
tion may be accepted, because fatty degeneration has been produced 
experimentally in animals whose temperature was mechanically raised 
by prolonged confinement in an oven. The alteration is supposed to 
be due to a lack of oxidation, since, under the influence of hyper- 
pyrexia, the red blood corpuscles take up less oxygen than normally. 

The steatosis occurring in grave anaemias, particularly that observed 
in progressive pernicious anaemia, has likewise been referred to a lack 
of oxidation. 

The same influence may be applied to other etiological conditions. 
The steatosis manifesting itself in the course of fevers, cachexias, and 
poisonings may always be explained by deficient oxidation. 

Finally, steatosis is observed when an organ is rendered inactive 
in consequence of suppression of nervous excitation, because metabo- 
lism does not progress in a normal manner. Nervous influence is in- 
dispensable for the regular performance of nutrition. If nutrition 
fails, oxidation diminishes and fatty degeneration is produced. The 
more active an organ is, the greater are its demands for oxygen. Con- 
sequently, if the supply of this gas be diminished, degeneration will 
affect first those parts which manifest the greatest physiological ac- 
tivity. Among the muscles, the myocardium is first attacked, then the 
diaphragm; among the glands, the liver and the kidneys. 

It is well to note that steatosis occurs when there is diminution 
but not suppression of oxidations. Stricture of an artery produces 
fatty degeneration; its obliteration, if not partially compensated 
by collateral circulation, results in necrosis. Suppression of oxida- 
tion ends in the death of the cellular element. 

The effects of steatosis may vary according to the organ attacked 
and the extent of the lesions. It is therefore not practicable to give 



CELLULAR DEGENERATIONS 323 

a general description of the process. In order to fix the ideas, let us 
consider only what takes place in the liver. 

Fatty degeneration of the liver occurs in a great number of cir- 
rhoses. Although the distribution of connective tissue serves as the 
basis for anatomical classifications, and to a certain extent rules 
symptomatology, the condition of the cell accounts for the evolution 
of the process. Atrophic cirrhosis is essentially a chronic affection. 
Hanot has described a variety which runs a rapid course, and causes 
death within four or five months. In this instance cellular alteration 
is profound and widely diffused; hence, the disease is called fatty 
atrophic cirrhosis. Likewise, the gravity of the fatty hypertrophic 
cirrhosis of Hutinel and Sabourin is due to cellular degeneration, 
which suppresses the function of the liver, and hence the process has 
sometimes been designated subacute icterus gravis. 

Although rapid, the evolution lasts for months in the examples 
just related. Such is no longer the case when a pathogenic cause in- 
duces an acute steatosis of the cells. The affection then runs its 
course in a few weeks, a few days, or even a few hours. This is what 
takes place in the process designated by the French as icterus gravis, 
and by the Germans as acute yellow atrophy of the liver. It is not 
a definite disease. As is well known, icterus gravis may occur in the 
most varied conditions and depend upon the most diverse causes (see 
page 203). Furthermore, an infectious or primary icterus gravis, 
a toxic icterus gravis, and a secondary icterus gravis occurring as a 
sequel of various affections of the liver, have been described. The 
classification of these dissimilar affections under one head is per- 
missible by virtue of the fact that the same lesion — namely, diffuse 
steatosis of the hepatic cells — exists in all of these morbid states. 
This lesion explains the symptoms. There is hepatic insufficiency, and 
the suppression of the functions of the liver, notably of its action on 
poisons, accounts for all the phenomena. 

The importance of fatty degeneration may be seen from these 
examples. It would be easy to repeat with respect to the various 
viscera what we have just stated concerning the liver. 

Amyloid Degeneration. — Amyloid degeneration was described by 
Eokitansky (1842) under the name lardaceous degeneration, by 
Christensen (1844) under the name waxy degeneration, and by Vir- 
chow (1853), who gave to it the name it now bears. In 1858 and 
1859, Kekule and Schmidt showed that amyloid matter is not, as 
might be supposed, an amylaceous substance. On the contrary, it is 
an albuminoid — i. e., a nitrogenous substance. 

In whatever locality it may be found, it is recognised by means of 
certain very simple reactions. Under the influence of the iodo-iodide 



324: INTRODUCTION TO THE STUDY OF MEDICINE 

test it gives a mahogany-red colour, which becomes violet red by the 
addition of sulphuric acid. On contact with methyl violet it be- 
comes red. 

Amyloid matter is perhaps normally met with in certain parts of 
the organism. It often constitutes an epiphenomenon in the course 
of the most varied affections, notably of nephrites. In certain cases 
it may be so widely distributed that amyloidism represents the prin- 
cipal manifestation. 

In the prostate gland and central nervous system of normal indi- 
viduals there have been noted concentric masses giving a mahogany-red 
reaction with the iodo-iodide reagent. It may be asked, Was amyloid 
matter really present ? Is it not more probable that these masses are 
simply collections of glycogenic matter? In answer thereto, it may 
be stated that the latter opinion prevails at the present time. 

As an epiphenomenon, amyloid matter occurs in blood extravasa- 
tions and in cicatrices. It is especially frequent in the kidney during 
the course of various lesions affecting this organ and of different 
varieties of nephritis, and even in acute nephrites. 

In all these instances amyloid degeneration is not widely distrib- 
uted; it has no clinical importance. Such is not the case with the 
facts which we will presently consider. 

Cohnheim has related cases where amyloid degeneration had in- 
vaded the organism without any cause being revealed to account for 
this alteration. Such an event is exceptional. Amyloid degeneration 
is nearly always secondary to diseases which are liable to induce 
cachectic conditions, such as tuberculosis, syphilis, and multiple sup- 
purations. 

Tuberculosis stands at the head of the list. Amyloidism is chiefly 
observed in patients suffering with pulmonary cavities, extensive 
lesions of the intestine, articular or osseous suppurations, necrosis, 
and caries. The foci almost always communicate with the exterior. 

Next comes syphilis, particularly hereditary syphilis, especially 
when the osseous system is involved. The spleen is the organ chiefly 
affected. 

Suppurations of long standing may give rise to amyloid degenera- 
tion. Sometimes arthropathies or osseous suppurations, sometimes 
visceral abscesses, dilatation of the bronchi, or multiple abscesses of 
the skin are the causative factors. Finally, of the rarer causes, we 
may mention cancer, especially ulcerated cancer, gout, rickets, alco- 
holism, and malaria. 

This etiological multiplicity makes it plain that all ages may be 
attacked. However, amyloidism is especially frequent in men and at 
the middle period of life — i. e., between twenty and thirty years. 



CELLULAR DEGENERATIONS 325 

Animals are not exempt from this degeneration. As in man, it is 
encountered in tuberculosis and in chronic suppurations. Krakow has 
succeeded in producing it experimentally. It is constantly observed 
in tuberculous pheasants, in the livers of which the tubercles are sur- 
rounded by a ring of connective tissue infiltrated with amyloid matter. 

It is to-day almost universally agreed that amyloid matter should 
be classed as of nitrogenous origin; but the mechanism presiding over 
its formation is as yet unknown. Wagner considers amyloid matter 
as intermediate between albumins and fats; and this view would 
explain the frequent coexistence of amyloid and fatty degenerations. 
Von Eecklinghausen believes a homogeneous matter is exuded from 
the cells, which coagulates on contact with the interstitial fluids. 
According to Ziegler, the diseased cells are unable to utilize the albu- 
mins escaping from the vessels, under which circumstances the albu- 
mins undergo a special metamorphosis. 

It is certain, however, that amyloid degeneration is decidedly 
analogous to fatty degeneration, for it is produced under the same 
conditions, and must therefore be considered as connected with a 
disturbance of albuminous nutrition. No further precision can be 
given to this somewhat vague formula. 

Amyloid degeneration affects the vessels and the connective tissue 
in a predominant if not an exclusive manner. 

In the arteries it begins in the inner coat, sparing the endothelium. 
It is especially marked in the middle coat. It extends to the capil- 
laries, which it transforms into vitreous, homogeneous tubes lined 
with endothelial cells, which remain intact. 

When it affects the organs, it presents three different macroscopic 
aspects. 

The totality of the greatest part of the organ is invaded; the 
tissue becomes homogeneous, semitransparent, lardaceous. At other 
times the process is limited to small foci having the appearance of 
sago grains. 

Finally, the lesions may be minute and recognisable only under the 
microscope or by transmitted light on thin sections treated with the 
usual reagents. 

The liver, which is the organ most frequently attacked, acquires a 
considerable volume. It becomes pasty, lardaceous, as if bloodless. 
Under the microscope, infiltration of the capillaries, hepatic artery, 
and, more rarely, of the portal vein is found. As to the changes in 
the cells themselves, discussion is still open. Some authors assert that 
degeneration occurs, others state that the vitreous masses encoun- 
tered are not altered cells, but amyloid masses that have exuded from 
the vessels. 



326 INTRODUCTION TO THE STUDY OF MEDICINE 

The localization is analogous in the other organs. In the spleen 
it is deposited in the Malpighian corpuscles ; in the kidney it is found 
in the vessels, glomeruli, connective tissue, and the walls of the uri- 
niferous tubules. The epithelial cells are frequently altered, but never 
amyloid. We may also mention the amyloid degeneration occurring 
in the lymphatic glands, the intestinal mucous membrane, and in the 
heart, where the muscle cells may be affected (Letulle and Mcolle). 

When amyloid degeneration is localized it does not give rise to 
any special symptoms. Thus, in parenchymatous nephritis, where it is 
almost constant, it is not expressed by any appreciable manifestation. 

When it is extensive it produces a certain number of phenomena, 
which vary according to its predominance in this or that organ. The 
first indications are paleness of the patient — i. e., paleness of the in- 
teguments and mucous membranes and loss of strength. 

Examination of the abdomen reveals considerable hypertrophy of 
the liver and spleen ; diarrhoea is very frequent ; the urine is remark- 
able for its abundance, pale colour, and the great amount of albumin 
which it contains, at least in certain cases. 

Though a fatal termination is the rule, it is, however, admitted 
that recovery is possible. The patient overcomes the cause that has 
produced the degeneration, and the latter subsides and finally disap- 
pears. Cohnheim, who has laid stress on this evolution, cites the 
following experiment : Fragments of amyloid matter, when intro- 
duced into the peritoneal cavity of an animal, are rapidly absorbed. 
Therefore, according to him, it must be concluded that absorption of 
this material may occur in the human organism. 

This experiment is interesting, since amyloid matter is very re- 
sistant. It is not altered when submitted to artificial digestion with 
pepsine and hydrochloric acid. In fact, these are the means gen- 
erally employed for its preparation. 

Pigmentary Degeneration. — A distinction analogous to what has 
been admitted in regard to fat must also be made for the pigments. 
Sometimes there is simple infiltration, sometimes degeneration. The 
cells may be charged with colouring matters, particularly the leuco- 
cytes, which are often overloaded with carbon even under normal con- 
ditions. In other cases the cells may be infiltrated by more or less 
modified blood pigment derived from former hemorrhage. Lastly, 
various black pigments, apparently derived from the blood, may also 
accumulate in certain anatomical elements without disturbing their 
function. 

In the case of pigmentary degeneration, on the contrary, cellular 
alterations are found which account for the disorders observed dur- 
ing life. 



CELLULAR DEGENERATIONS 327 

Pigmentary degeneration is essentially characterized by the accu- 
mulation within the cells of an okra matter (pigment ocre of Kelsch 
and Kiener, rubigine of Auscher and Lapicque), which has the prop- 
erty of turning black under the action of ammonium sulphydrate, 
or blue on addition of potassium ferrocyanide and dilute hydrochlo- 
ric acid. The latter reaction, which is very sensitive, is employed in 
histology. In preparations thus treated it may be seen that the pig- 
ment invades the protoplasm, pushes it aside, atrophies the nucleus, 
and causes its disappearance. 

All organs are not equally attacked. As is always the case, the 
frequency of the lesions is in proportion to functional activity. The 
liver is the organ most frequently invaded; next comes the kidney, 
then the myocardium and the pancreas. 

Pigmentary degeneration is chiefly observed in malaria, then in 
diabetes. It is much more rarely met with in pernicious anaemia, 
profound anaemias, and certain poisonings. It is a serious process, 
which, by virtue of the special cachexia it induces, may be placed 
parallel with amyloid degeneration. 



22 



CHAPTER XIX 
FUNCTIONAL SYNERGIES AND MORBID SYMPATHIES 

Unity of the organism in its physiological state: functional synergies — Unity of 
the organism under pathological conditions: morbid sympathies — Study of 
functional synergies : anatomical unity and physiological unity — The contigu- 
ity of organs — Vascular connections: emboli — Nervous connections — Conclu- 
sion concerning the mechanism of general reactions and of fever. 

Living organisms are constructed in such a manner that all modi- 
fication occurring at one point of the economy influences the entire 
economy. 

This law is equally true in physiology and in pathology. 

Let us suppose, for example, that a muscular group contracts. 
Circulation becomes at that point more energetic, and occasions con- 
sequently an increase of cardiac activity. But, in contracting, mus- 
cles consume carbohydrates, and when their reserve is exhausted the 
liver undertakes to furnish them with the useful materials; here is 
another organ entering upon activity. Kespiration will accelerate, 
since it must cause a greater amount of oxygen to arrive and throw 
out the excess of carbonic acid proceeding from the transformation 
of carbohydrates. Other wastes will be eliminated through the urine, 
and that will increase the activity of the kidney. Then, should con- 
traction be somewhat prolonged, bodily temperature will tend to rise, 
and the various apparatus concerned in the regulation of thermo- 
genesis will soon be called into play; there will follow vasomotor 
modifications and changes in the secretions, notably in the sweat. 
Finally, general nutrition being also stimulated, the result will be a 
loss of ternary and nitrogenous matters, and a tendency to repara- 
tion, as expressed by hunger and thirst, and consequently a general 
increase in functional activity. 

Eeciprocally, if an organ languishes, if its activity diminishes, the 
result is a series of reverse modifications in the entire economy — viz., 
a diminution in all the vital manifestations. 

Along with the relations which exist between the various parts of 
the organism and which constitute what is called in physiology func- 
328 



FUNCTIONAL SYNERGIES AND MORBID SYMPATHIES 329 

tional synergies, we find, in pathology, morbid sympathies or syner- 
gies. The disturbances may at first be local; on a superficial exami- 
nation, they seem to be limited to a part of the organism. In reality, 
a great number of modifications is necessarily produced in the whole 
economy. The reactions may be more or less marked, at times even 
imperceptible; they exist none the less. There is no disease that 
remains local. 

We are therefore led to inquire through what mechanism the 
lesions of an organ influence the remainder of the economy. For 
convenience of description, we may group in four classes the connec- 
tions uniting the various parts of the organism. These are func- 
tional synergies, contiguity of organs, vascular connections, nervous 
connections. 

Functional Synergies 

For the old idea, which assumed that each organ played a spe- 
cial and determined part, is substituted the more complex con- 
ception of functional synergies. We know at present that several 
organs collaborate in view of assuring the same function; that cer- 
tain organs may supply and replace each other in a more or less per- 
fect manner. 

As the result of physiological researches and clinical observations, 
parts which were separated by anatomical study have been united and 
grouped. Physiological unity does in no wise correspond to anatom- 
ical unity; thus, for example, the motor cell, the nerve, and the mus- 
cle represent the same physiological unity, whereas anatomy distin- 
guishes in them- at least three different parts. Pathology confirms 
the data of physiology on this point, since the alteration of one of 
these parts influences the others : destruction of the cell, for instance, 
entails atrophy of the nerve and muscle. 

In general, secondary alterations, consecutive to a primary lesion, 
produce an aggravation of the disease; but they realize at times 
a favourable modification and represent a tendency to a new adapta- 
tion. In the latter case the secondary lesions obey one of the two 
following laws : suppression of what has become useless ; anatomical 
or functional modification of parts capable of compensating for the 
primary lesion. 

These two laws are easily understood when the teachings of natu- 
ral history are taken into consideration. 

It is known, in fact, that function exists before the organ and rep- 
resents simply a reaction to an external cause; in the evolution of 
beings, every change means an adjustment to new needs. If external 
conditions vary, reactions must be modified. New functions are thus 



330 INTRODUCTION TO THE STUDY OF MEDICINE 

produced, which in time give rise to anatomical modifications, to the 
transformation of a pre-existing organ, or to the production of a new 
one. On the other hand, the organ can not maintain itself in its 
actual state unless the function that has given rise to its production 
continues to be exercised. 

It is well known, for example, that the eyes of moles and of some 
burrowing rodents are rudimentary, or may even be completely covered 
with skin and hair. Several Crustacea living in the subterranean 
caves of Carniola and Kentucky are blind. Darwin reports that in 
certain oceanic islands, where no carnivorous animals exist, birds are 
met with whose wings have become rudimentary and who are inca- 
pable of flying. In domestic ducks, the leg bones are more developed 
and those of the wings less voluminous than in the wild: another 
illustration of the law of adjustment. 

If we wish to look for analogous facts in the domain of embry- 
ology or ontogeny, we see that a series of organs disappear when they 
have become useless. The metamorphoses of certain batrachia, the 
atrophy or transformation of the branchiae, when the animal passes 
from aquatic to aerial life, shows us simply this adjustment of the 
organ to the function. 

What in this way occurs in a being who evolves, or what is ac- 
quired in successive generations and transmitted by heredity, is not 
different, on the whole, from that which is produced in an individual 
when physiological unity is affected at some point. 

Let us first take some very simple examples ; let us consider what 
happens in the vertebral column. Here is a physiological unity com- 
posed of a great number of independent pieces. Now, if one of these 
pieces be altered, as is the case in Pott's disease, there will consecu- 
tively be produced curves of compensation that will modify the shape 
of the whole vertebral column, will even reverberate in more distant 
parts — in the pelvis and thorax. These modifications are fortunate 
so far as they remedy the primary lesion and adjust the organism to 
new conditions, but they thus create a danger, and may become a cause 
of cardio-pulmonary accidents or of dystocia. 

Similar changes are observed consecutively to lesions of the hip, 
to the shortening of a member, to a defective position — that of the 
sciatic, for example — to some alteration of the skeleton ; there develop 
in the healthy parts more or less marked deviations of a compensative 
character, which respond to the first needs, but too often become the 
cause of new disturbances. 

The great systems, as the circulatory or the nervous, will furnish 
us illustrations of greater interest. 

Let us consider first what takes place in the circulatory system. 



FUNCTIONAL SYNERGIES AND MORBID SYMPATHIES 331 

In the case of a limited lesion, of ligation or obliteration of the 
main blood vessel of a member, a network of collaterals will develop. 
This result is favourable, since it permits the re-establishment of the 
circulation, but it sometimes creates new dangers, of which one may 
easily be convinced by considering the cases where the obliteration 
occurs in the principal vessel of a viscus. Thus, in atrophic cirrhosis, 
the disturbance of portal circulation, forcing the blood to pass through 
the channels of derivation, may be the starting point of oesophageal 
varices, and consequently the cause of a mortal hematemesis. 

The importance of secondary lesions clearly appears in the study 
of cardiac malformations. Congenital stricture of the pulmonary 
artery occasions persistence of the foramen of Botal, sometimes of 
the interventricular opening of the arterial canal, and the develop- 
ment of bronchial arteries. These various modifications always follow 
the same law, equally true in pathology, in physiology, and in natural 
history: re-establishment of functions on new bases and new adjust- 
ment, liable to become the starting point of new accidents. 

It is especially in the study of the nervous system that the history 
of secondary modifications abounds in interesting facts. 

The simplest illustration is represented by the neuromuscular sys- 
tem, including the cerebral cell, the medullary cell and the cord 
which connects them, the nerve, and the muscle; the lesion of the 
cerebral or medullary nerve cells entails degeneration of the sub- 
jacent parts. Eeciprocally, suppression of the muscles affects the 
nerve and the cells ; an amputation, for instance, gives rise to atrophy 
of the psychomotor centres corresponding to the suppressed part. The 
centres atrophy, because their peripheral expansions no longer exist : 
they have no longer any reason for being. Munck has experimentally 
realized similar facts : he has shown that extirpation of the eye causes 
atrophy of the optic centres. 

We find similar synergies when we consider the other apparatuses 
of the economy, such as the digestive and the genital. Extirpation 
of the ovaries leads to atrophy of the uterus; double castration acts 
similarly upon the prostate gland. 

In certain cases functional synergy allies parts that seem quite 
distinct : such is the alliance between the liver and the kidneys. The 
liver prepares certain materials necessary for the urinary secretion: 
nitrogenous substances undergo there an ultimate transformation 
which reduces them to the state of urea — i. e., a crystallizable body, 
which readily diffuses and represents a true physiological diuretic. 
If the uropoietic function of the liver is disturbed, the urea will be 
replaced by less oxidized bodies, some of which will prove harmful 
to the renal epithelium and give rise to a secondary nephritis. The 



332 INTRODUCTION TO THE STUDY OF MEDICINE 

hepatic lesion often leads to the passage into the general circulation 
of toxic substances, which the liver should have retained and trans- 
formed; or the principles of biliary secretion, salts and pigments, 
invade the economy; or else an excess of glucose reaches the blood. 
At all events, the kidney comes to the assistance of the organism 
and prevents intoxication; but the additional work imposed upon 
it may become the cause of epithelial alterations. These results, 
which we will study at greater length in connection with the lesions 
consecutive to dyscrasias, deserve to be alluded to here, since they 
clearly show what may be the consequences of functional synergies. 

These functional synergies are much more numerous than one 
might at first believe. As we are speaking of the liver, we know 
to-day that, through its glycogenic reserve, this gland plays a great 
part in nutrition; it regulates the supply for all the cells which con- 
sume sugar — namely, for all the cells of the organism. But it is 
especially with the muscles that the liver is in continual relation. As 
has been remarked by Chauveau and Kauf mann, " the liver is 
the indirect collaborator of the muscles in the execution of move- 
ments " ; when the muscle contracts, the liver pours the sugar more 
abundantly into the blood. It is then conceivable that disturbances of 
the glycogenic function should affect muscular contraction. 

Finally, there also exist altogether incomprehensible synergies be- 
tween various parts of the organism. Such is the relation existing 
between the genital apparatus on the one hand, and the pilous system, 
the larynx, and even the brain, on the other. It is known, for exam- 
ple, that the encephalon is far less developed in castrated than in 
entire horses. It is true that since the researches of Brown-Sequard 
there is a tendency to explain facts of this nature by internal secre- 
tions : the testicle or the ovaries are supposed to produce principles 
useful to the nutrition of these various parts of the organism. Some 
explain in the same manner the correlation which exists between 
the atrophy of the thyroid gland and myxcedema, the hypertrophy of 
this gland and exophthalmic goitre, the lesions of suprarenal capsules 
and melanodermia. The theory is very seductive, but in some re- 
gards it may still seem inadequate; at all events, if it were general- 
ized it would account for one of the most interesting aspects of func- 
tional synergies and their consequences — morbid synergies. 

Contiguity of Organs. — The lesions of one organ may affect 
neighbouring organs by two quite different procedures. Sometimes 
the action is simply mechanical: a hypertrophied viscus compresses 
and pushes away surrounding parts; in other cases the affection has 
specific characters and excites in adjacent parts special disturbances* 
or particular reactions. 



FUNCTIONAL SYNERGIES AND MORBID SYMPATHIES 333 

It will suffice to reflect for a moment on the anatomical disposi- 
tions of organs and their mutual relations, in order to understand the' 
effects produced by the peculiar development of any of them. Illus- 
trations abound; we shall recall a few: The exudation of the left 
pleura compressing mechanically the heart and the vessels, may occa- 
sion serious disturbances and even sudden death; thyroidal tumours 
crush the trachea; tumours of the uterus and ovaries push aside the 
intestines and the diaphragm, and disturb the play of the lungs. 

Phenomena produced by compression may be grave — e. g., the 
syncope resulting from left pleurisy; but the disturbances often dis- 
appear with the pathogenic cause. If pleurisy be punctured, the 
heart resumes its situation; if the tumours of the thyroid gland, of 
the uterus, or of the ovary be excised, the secondary manifestations 
stop. However, such is not always the case. A simple mechanical 
disorder may entail irremediable effects : compression exercised upon 
excretory passages, vessels, and nerves may produce a series of highly 
important modifications. 

Compression of the excretory duct of a gland causes stagnation 
of the secreted liquid. If compression be of short duration, the dis- 
turbances will cease when the obstacle is removed; but if it be some- 
what prolonged, a series of modifications in the epithelia, and con- 
secutively in the connective tissue, will appear. The obstacle may 
subsequently be removed, still the glandular lesion will persist and 
develop on its own account. The examples of this process are exceed- 
ingly numerous : we hardly need mention the cirrhosis produced by 
the compression of the biliary passages, the hydronephrosis, the scle- 
rosis and atrophy of the kidney, resulting from the obliteration of 
the ureter, as in the case of cancer of the bladder or the uterus. Simi- 
lar occurrences have been reported with reference to the salivary 
glands and the pancreas. We may also mention in this connection 
what occurs as the result of compression or stricture of the larynx and 
of the trachea : the lung is affected with an incurable emphysema. 

Similar phenomena are observed in the blood vessels; as a rule, 
they are even more rapid and more serious. If compression bears on 
an artery, the territory supplied by it becomes ischaemic, resulting in 
the production of necrosis or gangrene. In case of a vein, the blood 
stasis engenders oedema, and subsequently sclerosis. 

Compression of the nerves is expressed by sensory modifications, 
neuralgias, spasms, paralyses, vasomotor or trophic disturbances, at 
times by speedily mortal infections, best exemplified by the pneu- 
monia consecutive to section or compression of the pneumogastric 
nerve. 

When a compressing organ is struck with some inflammatory or 



334 INTRODUCTION TO THE STUDY OP MEDICINE 

neoplastic affection, it may, at the same time that it acts mechanically, 
exercise a specific influence. 

An inflamed tissue often occasions paralysis in subjacent parts. 
Stokes long ago established this fact as regards the diaphragm in 
cases of purulent pleurisy. Such is exactly the case when a phleg- 
monous angina causes paralysis of the palate. At other times, though 
this is more rarely the case, it is an acute pericarditis that causes the 
paralysis of the myocardium. What is produced in the striated mus- 
cles is equally observed in the nonstriated; such is gastrointestinal 
paralysis occurring in peritonitis. 

Inflammatory centres may be propagated to the surrounding or- 
gans. There sometimes occurs an unexpected opening of a purulent 
collection into a contiguous cavity. In most cases the opening is pre- 
ceded by a preliminary step — a true extension of the inflammatory 
process, giving rise to a thickening of the tissues, then to ulceration 
and perforation ; the pus thus makes its way toward the exterior. The 
process is often favourable, since it leads to the evacuation of the 
morbific matter; but it may become the source of new dangers, such 
as the abscess of the liver that opens into the lung and thus produces 
a pulmonary gangrene. 

Apart from microbic lesions, there are only cancerous affections 
that may thus be propagated by contiguity. The cancer of the stomach 
may cause secondary nuclei in the adjacent parts of the liver and 
pancreas. The cancer of the mammary and lymphatic glands may 
invade the skin, etc. In most cases, however, the propagation of can- 
cerous lesions is not effected in that way; the neoplastic cells, like 
pathogenic microbes, strongly tend to take the vascular (sanguineous 
or lymphatic) route, and to give rise in this way to foci more or less 
distant from the primary lesion. 

One might believe, in some cases, that sclerotic lesions have ex- 
tended in the same manner ; sclerosis of the liver and lung have been 
seen to follow perihepatites and pleurisies. But the process is far more 
complex: the visceral lesions are due, in cases of this kind, either 
to the direct action of the morbific cause, which acts both on the 
serous membrane and on the subjacent organ, or to the compression 
of the nourishing vessels which supply the viscus; the consequent 
anaemia, by disturbing the nutrition of the noble element, brings 
about the compensating development of connective tissue. 

Vasculak Connection's 

Cardiac Insufficiency. — Functional disturbances and lesions of 
the heart, leading to modification of the circulation of the blood; 
necessarily affect the entire organism. 



FUNCTIONAL SYNERGIES AND MORBID SYMPATHIES 335 

Vascular lesions, even those which seem to be best compensated, 
are attended by a certain number of vascular disturbances, and con- 
sequently by nutritive disorders. Examination of the facies in a per- 
son suffering with aortic or mitral lesion suffices to demonstrate the 
influence of the heart over distant parts. The dystrophic influence of 
cardiopathies is especially marked when the lesion has begun in child- 
hood; it may be expressed by infantilism, as is at times observed 
as the result of aortic insufficiency. A better-known example is fur- 
nished by the history of simple mitral stenosis, giving the women 
affected with it a chlorotic appearance. 

However, where the pathogenic influence of circulatory disturb- 
ances appears most clearly is in cases of cardiac insufficiency or 
asystole. 

This process is essentially characterized, from an anatomical and 
clinical point of view, by a weakening of the myocardium and insuf- 
ficiency of the tricuspid valve; from the standpoint of pathological 
physiology, by a diminution in the arterial and an increase in the 
venous tension. The result is a stasis in the organs, the liver, kid- 
neys, and brain. If then treatment intervenes, if digitalis is admin- 
istered, the contractile energy of the myocardium increases, and all 
the symptoms disappear; the arterial tension returns to its normal 
condition; the liver, which had increased in volume, diminishes; the 
kidney no longer permits the escape of the albumin ; the urine returns 
to its normal quantity; the cedemas disappear. The patient be- 
lieves himself re-established and resumes his occupation, but after 
a certain period of time a second attack of asystole occurs, then a 
third, then a fourth. Finally, there comes a moment when no good 
result can be obtained from the administration of digitalis; the con- 
gestion of the organs admits of no relief, the liver remains hyper- 
trophic, the kidneys continue to pass out albumin, the cedemas per- 
sist. What has happened? 

In the former case, when all disappeared under the influence of 
cardiac medication, the question was of an individual in whom the 
functional modifications of the organs were under the influence of 
cardiac insufficiency; it was therefore sufficient to increase the en- 
ergy of the myocardium by means of digitalis, caffeine, or sparteine 
to see the accidents vanish. But when the morbid manifestations 
were repeated, they at length disturbed the function of the organs; 
the visceral congestions were followed by more profound alterations; 
the cells degenerated, and secondary scleroses were produced. Asys- 
tole has yielded to cardiac cachexia. Let us suppose that it was pos- 
sible to replace the diseased heart by a normal one; the symptoms 
would continue none the less, because the primary disturbances of 



336 INTRODUCTION TO THE STUDY OF MEDICINE 

the circulation have created, secondarily, organic lesions which evolve 
on their own account; the cardiac has become a pulmonary, a cere- 
bral, a hepatic, or a renal patient. In many instances the secondary 
lesions are so predominant that the clinician is at a loss to trace the 
succession of the phenomena; in vain he endeavours to determine 
what has been the primum movens of the morbid series. 

Are these secondary accidents to be attributed to the venous stasis 
resulting from the cardiac insufficiency, and can they be accounted 
for merely by hydraulic modifications? If such were the case, the 
viscera would have been altered according to a determined order; the 
inferior cava system, which empties itself with more difficulty than 
the superior, would first be affected, and among the viscera that 
are annexed the liver would be the first to receive the blood reflux 
from the right auricle ; it would, then, be affected before the kidneys, 
whereas the brain would be reached after the abdominal organs. Clin- 
ical experience shows that such is the case with children; in childhood 
visceral asystole begins with the liver, and albuminous urine is 
scarcely ever' observed without hepatic hypertrophy. But such is 
not the course of events in adults. The reason of this divergence 
is easily comprehended. In the child the organs are healthy; they 
have not been altered by the numerous infectious or toxic agents which 
in the adult have left in the viscera traces of their passage. Previous 
diseases create local susceptibilities, particular vulnerabilities; hence, 
in presence of the same morbific cause, each organ suffers on its own 
account, with the result that more mutability of symptoms, more 
unexpected morbid reactions, and more variability in clinical types are 
observed. This is the reason why visceral lesions consecutive to 
cardiopathies do not follow, in the adult, the regular course observed 
in the child; that is why we meet with pulmonary, hepatic, renal, 
or cerebral partial asystoles. If we were able to know exactly the 
past of our patients, if we could find out what defects they have 
inherited, if we could succeed in determining what organs had been 
touched and to what degree altered, we would be in a position to 
predict assuredly what are to be the localizations of cardiac insuf- 
ficiency. 

We have hitherto supposed the cardiac lesion to be primary; but 
such is not always the case. Through the vessels terminating in or 
starting from it, the heart finds itself in communication with all 
the parts of the organism, and therefore it is readily influenced by 
them. 

If any disturbance is produced in the intrapulmonary circulation, 
as it occurs in bronchial dilatation and in pulmonary sclerosis or. 
emphysema, the right heart, compelled to do some additional work, 



FUNCTIONAL SYNERGIES AND MORBID SYMPATHIES 337 

will in the end dilate, and tricuspid insufficiency and the phenomena 
of asystole will follow. The same result is observed in tuberculosis, 
or, at least, in one of its forms known as fibrous phthisis; in this 
case emphysema and bronchiectasis exist, and it is to these various 
lesions that the cardiac disturbances must be attributed. 

Asystole of pulmonary origin often presents, clinically, some par- 
ticular characters : the pulse may be strong, regular, and arterial ten- 
sion sufficiently high; there is then an evident discordance between 
the state of arterial circulation and the symptoms observed. The 
reason is that the hepatic hypertrophy, albuminuria, oedema of the 
lower extremities, depend upon the disorders of the right ventricle, 
and, in fact, it is the latter that is primarily affected, while the 
left ventricle continues to contract with sufficient energy. There is 
discord between the condition of the two halves of the heart. This 
fact explains why so little result is obtained from treatment with 
digitalis, which influences especially the left heart. 

Organs other than the lung may influence the heart and bring 
about through it a series of new disturbances; this is observed in 
the kidney and the liver. We see, for example, Brightics present 
cardiac disturbances as initial phenomena; others succumb to asys- 
tole. 

Paet played by Pekipheeal Blood Vessels 

Outside of the heart, peripheral blood vessels establish numerous 
connections between the various parts of the organism, and explain 
a great number of secondary disturbances. 

Organs may be brought into relation by a particular blood sys- 
tem. Such is the case with the portal vein. It is conceivable, when 
the anatomical disposition is taken into account, that alterations 
affecting the spleen, the stomach, the intestine, may disturb the cir- 
culation of the liver. In most cases the reverse takes place — a hepatic 
cirrhosis causes congestion of the digestive canal, hypertrophy of the 
spleen, development of a collateral circulation, and production of 
ascites. 

In other instances, by far more numerous, the secondary disturb- 
ances result from the compression exercised on the vessels of an 
organ by the parts with which the latter are in relation. 

The effects evidently vary according as the compression is exer- 
cised on the afferent vessels (artery or portal system) or on the 
efferent (veins or lymphatic vessels). In the former case there is 
ischgemia or complete anaemia, in the latter a venous or lymphatic 
stasis. In consequence of this first stage, circulatory modifications 
may supervene, tending to re-establish the blood course and thus 



338 INTRODUCTION TO THE STUDY OF MEDICINE 

remedying the first accidents. Otherwise, the compression will cause 
modifications of a trophic order : sometimes dystrophy will attack the 
vessel itself and produce hemorrhage; sometimes persistent ischaemia 
will terminate in necrobiosis and softening ; finally, in other instances, 
venous or lympatic stasis will engender sclerosis. But in the last 
case we must, perhaps, as we have done with regard to cardiac insuf- 
ficiency, assume the intervention of some superadded element — i. e., 
microbes or their toxines. Sclerosis would then depend upon an in- 
fection sufficiently attenuated not to give rise to any appreciable 
manifestations. 

Such is not always the case; vascular disturbances often favour 
the development of serious infections. They play an important part 
in the pathogeny of diffused phlegmons, of dry or moist gangrenes; 
they constantly intervene in the localization of even specific pro- 
cesses : such is caseous pneumonia in those cases where the pulmonary 
artery is narrowed and compressed by a tumour or aneurism of the 
aorta. 

In this manner, any lesion whatever which compresses the ves- 
sels of an organ produces a series of consecutive modifications, which 
may be summed up as follows: initial disturbances of circulation, 
anaemia or passive congestion, more or less complete re-establishment 
of circulation, sometimes development of collateral networks, or con- 
secutive trophic disorders, necrobiosis, softening, sclerosis, and possibly 
pyogenic, gangrenous, or tuberculous secondary infections. 

The circulatory system plays also an important part in the 
propagation and diffusion of morbid processes, serving as a vehicle for 
soluble products or foreign bodies springing from a primary focus. 

We shall not dwell upon the diffusion of soluble products, of which 
we have already repeatedly spoken. We have shown that every cell 
constantly modifies the chemical constitution of the blood and thus 
influences the remainder of the economy. Each living element acts 
by seizing upon the substances necessary to its nutrition, by abandon- 
ing products of disassimilation, by secreting substances which con- 
tribute to the regulation of nutrition, finally (at least in certain 
cases), by neutralizing toxines and throwing them out or by producing 
antitoxic substances. All these products, favourable or unfavourable, 
are poured into the circulation and by means of vascular connections 
are carried to the various parts of the economy. They act on the 
first organ with which they come into contact. Thus, toxines 
proceeding from the digestive canal meet with the liver and occa- 
sion in this gland congestion and sclerosis. But the arrest is not 
complete ; a certain quantity crosses the first barrier and diffuses into- 
the economy. Now there are certain organs better situated than 



FUNCTIONAL SYNERGIES AND MORBID SYMPATHIES 339 

others for mutual influence; such is the case with the liver and kid- 
neys. The toxines originating from the liver easily go to alter the 
renal filter, as was demonstrated by the researches of Gouget; recip- 
rocally, the diseased kidney affects the liver, as was shown by Hanot 
and Gaume. Finally, recent researches have established the fact that 
the lesions of the lung rapidly produce secondary alterations in the 
liver. It would be easy to multiply the examples. Let us keep well 
in mind that through the circulatory system soluble substances are 
transported to the whole organism, but that they do not act equally 
upon all the parts. Their action is particularly manifest on the organs 
which are found in direct relation through the vessels, and on cer- 
tain cells belonging to different organs but allied to each other 
by virtue of functional synergies. 

Besides the soluble products, the circulatory system may carry solid 
bodies, which go on unobstructed until the moment when, meeting 
with too narrow a vessel, they are forced to stop at once. To this 
process has been given the name embolism; its importance leads us 
to describe it somewhat in detail. 

Embolism. — To Van Swieten is due the merit of having discovered 
embolism and made of it a complete study, both clinical and experi- 
mental. But men were not prepared for the new conception, and 
the labours of Van Swieten remained unnoticed or fell into oblivion; 
the discovery had arrived too soon. 

In the following century, when Virchow published his works on 
embolism (1845-^56), physicians, prepared therefor by some re- 
searches of Magendie, Gaspard, d'Arcet, and Cruveilhier, accepted with 
enthusiasm the ideas of the celebrated anatomico-pathologist. The 
question was taken up at the right moment; it led to a series of in- 
vestigations which secured a rapid progress for its study. 

Embolism is generally defined as sudden occlusion of a vessel 
by a foreign body travelling in the circulatory system. The meaning 
of the word has of late been modified; some have described under 
the same name incomplete obliterations, and others have spoken of 
microbic emboli, or of foreign bodies, extremely small, unable even 
to obstruct a capillary. The latter stop by virtue of a molecular adhe- 
sion which retains them, as are retained microbes in a porcelain filter 
whose pores are larger than they. 

We are thus conducted to the following definition: Embolism is 
essentially characterized by the sudden arrest of a foreign body car- 
ried by the sanguineous or lymphatic circulation. 

Emboli are divided, according to their volume, into emboli of large 
and small calibre and into capillary emboli; according to their point 
of departure, into exogenous and endogenous emboli. The former pro- 



340 INTRODUCTION TO THE STUDY OF MEDICINE 

ceed from the exterior, the latter originate within the economy. 
Finally, in view of their nature, they are divided into mechanical or 
inanimate and parasitic or living emboli. 

It is now easy to take into account the various divisions of the 
general classification. We are thus led to group emboli as follows : 

Emboli 
Inanimate. Living. 

Of intravascular origin. Animal. 

Cardio-vascular. Vegetable. 

{Clot. Microbic. 

Globules. Cancerous. 

Colouring matters. 
Of extravascular origin. 
Solid. 
Fatty. 
Cellular. 
Gaseous. 

Inanimate Emboli do not act, in most cases, except in a me- 
chanical way. They may be engendered in the walls of the heart or 
of blood vessels. Small vegetations emanating from an endocarditis, 
fragments of columns or of valves, atheromatous productions occu- 
pying the coats of large vessels, fall into their interior and are car- 
ried by the blood current. 

The second group is represented by blood clots detached from 
the inner surface of the heart or of blood vessels, where they had 
been deposited under various pathological conditions. In endocarditis, 
arteritis, and notably aortitis, cruoric or fibrinous clots, frequently 
lining the altered wall, may at a given moment engender emboli. The 
same process is quite often observed with the aged in the auricle. 

More frequently the difficulty is with a vein; its walls, invaded 
by a microbe, are inflamed, become rugged, and lead to the formation 
of a clot. The blood, stagnating behind this obstacle, coagulates in 
its turn, and engenders a secondary soft clot, the so-called elongated 
clot, which will extend to the point where the vein joins a main trunk. 
It will extend even beyond the junction, penetrating into the lumina of 
the vessel; in this way it forms a projection compared to the head 
of a nail, which, constantly beaten by the blood current, will easily 
be detached. In other cases there is an adhesion of one of the pri- 
mary or secondary clots, which is not sufficiently firm, and often, 
at the time when the patient is about to recover, when he moves 
and begins to rise, the clot breaks up. More or less voluminous 
fragments are detached and, being thrown into the circulation, give 
rise to embolism. 

Other varieties of emboli may be produced in the blood. Altered 



FUNCTIONAL SYNERGIES AND MORBID SYMPATHIES 341 

red blood corpuscles represent veritable foreign bodies that will go 
to plug capillaries and occasion in the organs the most varied lesions. 
This is observed in cases of poisoning by oxide or sulphide of carbon, 
chlorate of potash, or chloroform. If the destroyed corpuscles are 
somewhat numerous, extended lesions are produced in certain viscera. 
In this way are explained the small centres of cerebral softening which 
occur quite frequently in intoxication by carbonic oxide. 

Globular emboli are produced also in extensive burns and frost- 
bites, and explain certain phenomena. In the focus, the red cor- 
puscles are altered, destroyed ; when carried by the blood current, they 
produce embolism. Their action is completed by the hematoblasts 
which contribute to the formation of venous thromboses, followed 
secondarily by visceral emboli. 

Matters derived from the red corpuscles may form emboli, as 
occurs, at least, in cases of malaria. Without admitting, with Fre- 
richs, that the genesis of the pernicious manifestations is due to 
pigmentary emboli, we must recognise that the pigment emanating 
from the spleen and from the marrow of bones may induce various 
alterations in other organs. 

Inanimate emboli, engendered outside of blood vessels, are repre- 
sented, first, by solid foreign bodies; this variety has but an experi- 
mental interest. In order to study the mechanism of emboli, experi- 
menters have repeatedly injected into the vessels little balls of wax 
and inert powders, especially lycopodium powder. An interesting 
group is represented by the cellular emboli that originate within the 
economy; they are due to the penetration of dead cells or even tissue 
fragments into the vessels. This is particularly observed as the result 
of great traumatisms. In cases of hepatic contusion particles of the 
wounded gland were seen to be carried to the heart and pulmonary 
artery. Similar phenomena have occurred in cases of puerperal 
eclampsia and have been explained by the existence of a hemorrhagic 
hepatitis. Euge has called attention to the emboli of cerebral matter 
which may occur in the lungs of the newborn, when the head has been 
strongly compressed by the forceps, especially in cases of narrow 
pelvis. 

In general, simply the contents of the cells, especially the fat, 
are thrown into the circulation. 

In this manner, according to Virchow, are produced, during con- 
finement, fatty emboli in the kidney and lungs; they are supposed to 
be due to contusions of the cellular tissue of the abdomen and 
vagina. At times the fat starts from an organ that has undergone 
fatty degeneration — from the liver, for example — and gets fixed in a 
branch of the pulmonary artery or in the kidney. Fatty emboli are 



342 INTRODUCTION TO THE STUDY OF MEDICINE 

particularly frequent in the lesions of the osseous system. They are 
produced in all fractures, according to Scriba. More frequently, they 
originate from osteomyelitis. Of slight gravity when they are not 
abundant, they may, when repeated, produce pulmonary accidents and 
sometimes entail speedy death. 

Fatty emboli have been observed also in diabetes, but their mech- 
anism is not understood; according to Hamilton and Saunders, ace- 
tonemic coma is to be attributed to them. 

Gaseous emboli are nearly always exogenous. They have some- 
times been produced by the surgeon during a transfusion or an intra- 
venous injection. If the amount of air introduced is not too consid- 
erable, there results no harm whatever; if the air enters suddenly 
and in great quantity, the patient succumbs within a few minutes. 
Similar accidents have occurred when, in the course of an operation, 
one of the jugular veins is cut and, being maintained gaping by the 
cervical aponeuroses, suffers the effects of thoracic aspiration: the air 
enters into it with a special hissing sound. The same phenomenon 
has been observed in the uterus in cases of placent praevia: the air 
penetrates through the gaping sinuses. 

In some exceptional cases gaseous embolus has been endogenous. 
Jurgensen has seen, in the course of a round ulcer, gas penetrating 
the vessels; he was able, during life, to recognise its presence in 
the left temporal and the external jugular. 

Animate Emboli represent a group still more important than 
the one we have first studied. They explain the propagation of 
animal parasites, such as hydatid, strongylus, fllaria, or Distoma 
hepaticum. In cases of hydatid the embryo passes from the digestive 
canal into a branch of the portal vein, and it is by a true embolic 
process that it will go to fix itself in the liver. 

The role of embolism in the evolution of lesions produced by 
vegetable parasites is not less notable. 

Let us take, for example, actinomycosis: the primary focus may 
give rise to secondary, sometimes multiple lesions, which in some 
cases are sufficiently numerous to make us think of pyasmia. The 
same is true of cases of aphtha, and this result is comprehensible, 
since Wagner has shown that the oidium sends out projections into 
the vessels of the mucous membrane. In this way is explained the 
formation of visceral foci, as such examples have been recorded by 
Zenker and Eibbert. 

But it is especially in the generalization of infectious lesions that 
embolism intervenes. If we can no longer admit, with Toussaint, that 
microbes cause death by plugging the capillaries, it is certain that they 
often produce, by this mechanism, secondary foci. This is what 



FUNCTIONAL SYNERGIES AND MORBID SYMPATHIES 343 

takes place in cases of pyaemia. Starting from a primary lesion, 
pathogenic agents are capable of penetrating directly into the blood; 
in most cases they first give rise to phlebitis, whose importance in 
the dissemination of lesions and the production of purulent infec- 
tion was noticed by old observers. The clot which microbes have 
colonized breaks up and its particles are thrown into the circulation. 
Microscopic emboli are produced which do not act only in a mechan- 
ical manner; they carry living germs which give rise to the develop- 
ment of secondary foci; the latter present the same character as 
the primary focus. 

In certain instances, when the secondary lesion communicates with 
the external air, germs proceeding from the exterior may ultimately 
be introduced and transform the purulent into a gangrenous focus. 
This sometimes occurs in the lung. 

Many other infections are propagated by the same mechanism. 
Such is the case with glanders and, particularly, tuberculosis. In 
the acute miliary forms, generalization is often consecutive to an old 
caseous focus; at that point is produced a specific phlebitis which 
permits the dissemination of the germs. 

By the same process cancer is propagated. Whether this disease 
be, or not, parasitic, it is certain that the neoplastic cells behave 
exactly as parasites. They penetrate the more easily into the ves- 
sels, as they possess, when young, amoeboid movements (Waldeyer). 
The study of the secondary cancer of the liver permits us to under- 
stand this process and to follow the evolution of the cells arrested 
in the capillaries of the organ; as it has been well demonstrated 
by Hanot and Gilbert, it is the wall of the capillaries that forms the 
stroma of the neoplasm. The same mechanism may be applied to 
other secondary cancers, notably to those of the lung. We could easily 
multiply the examples ; they establish that the secondary foci, through 
the cells which they contain, repeat the primary focus, and, by their 
structure, recall the anatomical character of the organ in which they 
are developed. 

Course of Emboli. — Whatever their nature, emboli follow a route 
traced in advance and governed by the laws of the circulatory me- 
chanics. From this point of view they may be divided into three 
groups: arterial emboli, pulmonary emboli, and emboli of the portal 
system. 

Arterial emboli start from some lesion of the pulmonary veins, 

of the left heart, of the aorta or one of the vessels emanating from 

it. If, as is most frequently the case, they are born before the aorta 

or at its origin, they pass generally into the left common carotid, 

whose direction continues that of the arch; they stop in the Sylvian 
23 



344 INTRODUCTION TO THE STUDY OF MEDICINE 

and produce right hemiplegia with aphasia. This takes place in half 
of the cases. 

In other instances, continuing its route in the aortic trunk, the 
embolus is arrested in the splenic, in the renal, at times in the iliac 
artery, especially in that of the left side, the blood current being, it 
is said, hindered in the right iliac by reason of the passage in front 
of it of the corresponding vein. More rarely, embolism will occur 
in the subclavian or in the mesenteric arteries, or in the cceliac axis ; 
it has exceptionally been observed in the bronchial arteries, in the 
hepatic artery, in the arteries of the bones, of the spinal cord, etc. 

If the embolus has taken rise in the peripheral venous system — for 
example, in the femoral vein — it is readily understood that it will 
go through the inferior vena cava and, passing through the right 
heart, will enter the pulmonary artery and stop in the capillaries 
of the lung. In this way is produced pulmonary embolism in con- 
nection with the lesions of the peripheral veins or of the right heart. 

Lastly, if the embolus starts from the intestine, it will enter the 
portal vein and go to the liver; then, if the hepatic barrier is crossed, 
it will follow the same route as in the previous case. There will 
be secondary pulmonary embolism. 

Such is, as it were, the normal course of an embolus. There are, 
however, cases in which the foreign body does not follow the blood 
current. Such are the cases of paradoxical emboli. 

The embolus, starting from a vein, instead of stopping in the 
pulmonary vessels, reaches the aortic system. This fact has been ex- 
plained in two different ways. Weber supposes the existence of par- 
ticular canals connecting the pulmonary arteries and veins, which 
canals, being larger than the capillaries, are easily traversed by small 
foreign bodies. Others have assumed a different mechanism, accord- 
ing to which the embolus, originally very small, passes the lung, then, 
by a mechanism similar to that of a snowball, accumulates fibrine and 
acquires a size larger than that of the vessels through which it has 
passed. 

It seems, at present, that another explanation is to be accepted. 
Since the researches of Zahn, it is established that the foramen of 
Botal is not obliterated in one fifth of normal individuals (139 times 
out of 711 hearts examined). A communication, therefore, persists 
between the two auricles, which fact explains how an embolus can 
easily pass from the pulmonary into the general circulation. 

Finally, there are described, under the name retrograde emboli, 
those whose course is in an opposite direction to the blood current. 
These are explained by the disturbances produced at the moment t of 
thoracic aspiration, and particularly by efforts of coughing; it is thus 



FUNCTIONAL SYNERGIES AND MORBID SYMPATHIES 345 

conceived how microbic emboli are quite often engendered in the 
hepatic veins. 

Lymphatic Emboli. — Side by side with blood emboli may well be 
placed lymphatic emboli. The latter may, from the standpoint of 
their nature, be divided into mechanical and animate. Among the 
former, we shall note only the colouring matters introduced beneath 
the skin by tattooing, and particles of carbon and dust inhaled by 
the lungs. Being carried into the lymphatic current, these small for- 
eign bodies are stopped in the glands. These organs thus play a 
protective part for the organism. Their intervention is still more 
marked in infections; the lymphatic glands often oppose to microbes 
a very resistant barrier. In the case of malignant pustule, for in- 
stance, the disease remains local and curable if the glands corre- 
sponding to the inoculated region resist; if they are crossed, blood 
infection is produced and entails death. Likewise, in tuberculosis, 
adenopathies tend to prevent the dissemination of the bacilli ; in many 
apparently healthy subjects there are found in the tracheo-bronchial 
glands tubercle bacilli which remain located there without giving 
rise to any bad results. 

The invasion of the glands, in cases of cancer, is explained by the 
same mechanism, and finds also its reason for being in a tendency 
of the economy to circumscribe the disease. Too often, however, the 
invasion of the glands is the starting point of new lesions; the neo- 
plasia diffuses out of the lymphatic apparatus; in this way cancerous 
foci may be produced in the pulmonary hilum, consecutively to 
adenopathies of the same character. 

Let us note, finally, that retrograde emboli may occur in the 
lymphatic as well as in the blood system; they are met with in the 
thorax, and are supposed to account for certain cases of pulmonary 
cancer. 

Effects of Embolism. — The effects of embolism vary according to 
the point where stops the foreign body. Arrest may occur in the 
heart, especially in the right heart. In this case sudden death is fre- 
quently observed. A reflex syncope is produced, owing to a violent 
excitation of the endocardium. 

More frequently the foreign body reaches the pulmonary artery. 
The effects vary with its size. 

If its proportions are considerable, the individual may succumb 
suddenly; a syncope is produced by a reflex action starting from the 
liver. If the embolus is small, it stops in a branch of the pulmonary 
artery; the occlusion of the latter is followed by an intraparenchym- 
atous hemorrhage known as pulmonary apoplexy, or, still better, 
hemoptoic infarctus. 



346 INTRODUCTION TO THE STUDY OF MEDICINE 

In the majority of cases the infarcts are multiple, more numer- 
ous in the right than in the left, mostly in the lower and posterior 
parts of the lung. When they are cortical they have the form of a 
cone whose base is situated beneath the pleura; they are rounded in 
the interior of the parenchyma. These infarcts are easily recognised 
by their dark colour, comparable to that of truffles, and by the resist- 
ance they offer when palpation of the lung is practised. 

Three theories have been put forth to explain their formation. 
Virchow assumes a diapedesis of red corpuscles, Cohnheim a vascular 
rupture resulting from the venous stasis. Eanvier, whose opinion is 
generally admitted, thinks that there occurs a necrobiosis of the 
arterial wall, and, secondarily, a hemorrhagic sweeping off; it is thus 
conceivable that there should pass twenty-four to thirty-six hours 
between the occlusion of the vessel and the hemorrhage. 

The pulmonary infarcts are expressed by two classes of symp- 
toms; some of them make us suspect the lesion; the others permit 
us to affirm its existence. 

Among the signs of presumption we will mention dyspnoea, which 
sometimes assumes disquieting proportions. The physical signs are 
of little importance : at times a focus of rales with small bullae is 
found, and at other times a silent zone surrounded with small rales, 
and sometimes a murmur is heard. 

The true symptom, that which permits recognition of the lesion, is 
hemoptysis. The sputum of the patient is thick, dark, viscous, non- 
aerated, adhering to the cuspidor, and exhaling a sour odour com- 
parable to that of antiscorbutic sirup. This expectoration, so char- 
acteristic, lasts for five or six days, even when embolism does not 
recur. It differs considerably, therefore, from the bronchial hemop- 
tysis of the consumptives, which is characterized by the rejection of a 
red, aerated, spumous blood, and not continuing when hemorrhage has 
ceased. 

It may occur, finally, that the emboli be altogether minute; they 
occasion in the lungs small punctiform hemorrhages, one interesting 
variety of which constitutes the festooned diffuse infarctus of Eenault. 
These lesions are not rare in cardiac patients, and are expressed 
simply by the appearance or aggravation of dyspnoea. 

The various lesions produced by the emboli of the lungs may be- 
come cicatrized and infiltrated with calcareous salts. At times thev 
are invaded by external microbes, become softened, or even — though 
this is exceptionally the case — undergo gangrenous transformation. 

The effects of arterial embolism differ from those observed in the 
system of the small circulation ; they vary also according to the organ 
under consideration. 



FUNCTIONAL SYNERGIES AND MORBID SYMPATHIES $4:7 

In most cases, as already stated, the embolus enters the left com- 
mon carotid and is stopped in the Sylvian. If the occlusion occurs 
in the principal trunk, an extensive softening is the result; the 
hemisphere is transformed, as it were, into pap; the central parts, 
optic thalami, and corpora striata alone resist, because their circula- 
tion is assured by special blood vessels. 

In general, only one branch is affected. If it is one of the short 
arteries, destined for the cortical part of the brain, a superficial patch 
of cortical softening is formed; if a long artery is struck, the focus 
occupies the white substance. 

Clinical as well as experimental researches permit us to follow very 
regularly the mode of formation of the lesions. In the beginning a red 
softening is produced; subsequently, the colouring matter of the 
blood being transformed, the focus becomes yellow, and finally white. 
In the end, if its seat is on the surface, it assumes the aspect of 
yellow, hard, sclerous patches. If it is central, it suffers a more 
marked softening; the white substance liquefies and presents the 
appearance and consistency of lime milk; at times the lesion becomes 
encysted and forms a sort of foreign body. 

Large cerebral emboli may give rise to a rapidly fatal attack of apo- 
plexy. Those of medium and small size often produce a transitory apo- 
plexy, followed by permanent disturbances which vary according to the 
site of the lesion; aphasia and paralysis of the face or the extremities 
are connected with the cerebral department which has been affected. 

Lastly, when emboli are extremely minute, only headache, dizzi- 
ness, and some mental disturbances are observed; however, should the 
emboli be repeated, they may entail coma and death. 

Of the other arterial emboli, we may cite that of the central artery 
of the retina, which is expressed by a sudden amaurosis ; on ophthal- 
moscopic examination, the papilla is found pale and the arteries con- 
tracted. 

If the embolus passes into the abdominal aorta, it may reach the 
spleen, where it produces an infarctus, expressed by a sufficiently in- 
tense pain in the left side. In other instances it stops in the kidney 
and causes lumbar pain and mild hematuria. 

Among the other vessels that may be affected, we will first cite the 
coronary arteries of the heart. If the embolus is small, it gives rise 
to angina pectoris, this syndrome appearing whenever cardiac circula- 
tion is hindered. If the embolus is more voluminous, the occlusion 
of the coronary results in sudden death by rupture of the heart. 

Finally, when the artery of a limb is obstructed, circulation stops 
there, the pulse is suppressed, the skin grows cold and pale and is in- 
vaded by external germs, which produce in it dry gangrene. 



348 INTRODUCTION TO THE STUDY OF MEDICINE 

Among the emboli that act mechanically, the fatty and the gaseous 
deserve special mention. 

Fatty emboli are observed consecutively to osseous lesions. When 
a great traumatism has caused some serious fracture, fat often passes 
into the blood in considerable quantities; some of it stops in the 
lung, the remainder invades the general circulation, and may obstruct 
the vessels of the brain or bulb. Under these conditions a violent dysp- 
noea is observed, which, after a sudden onset, progressively increases 
and ends in death. Its differential diagnosis from nervous shock lies 
in the fact that in the latter case the manifestations are at their maxi- 
mum at once, while in the former they progressively aggravate. 

Gaseous emboli are produced particularly when, in the course of 
an operation, air penetrates a vein. A characteristic hissing sound 
is then heard, the patient grows pale, and dies suddenly. If life is 
prolonged, there is sometimes heard, on auscultation of the heart, a 
special murmur (the so-called bruit de moulin) produced by the 
mingling of air with the blood. 

Generally attributed to obstructions of the pulmonary vessels, the 
symptoms of gaseous emboli have been ascribed by Brown-Sequard to 
bulbar emboli. It is certain that when operating upon animals we 
notice that the gas readily passes through the lung and invades the 
general circulation. The experiment succeeds well with the dog; by 
operating slowly one may, without causing any accident, introduce 
into the veins a considerable quantity of air. After the animal is 
killed, it is found, at the autopsy, that all the arterial system is filled 
with small gas bullae. 

Leaving aside the paradoxical and retrograde emboli, we resume in 
the tabular representation on the opposite page the course and effects 
of the principal mechanical emboli. 

Nervous Connections 

Along with functional synergies, contiguity of organs, and vas- 
cular relations, we must take into account, as already stated, the con- 
nections established by means of the nervous system. After the de- 
tails given in connection with nervous reactions, we shall only briefly 
consider this last part of our subject. 

The lesion of an organ may, by compressing a nerve, give rise to 
disturbances in distant parts. A tumour of the mediastinum, an 
aneurism of the aorta, affecting the sympathetic or the recurrent, 
produce pupillary or laryngeal disorders, which might lead the inex- 
perienced to an error of diagnosis. 

In other instances the question is one of reflex phenomenon, ter- 
minating in motor, sensory, vasomotor, and secretory disturbances. 



FUNCTIONAL SYNERGIES AND MORBID SYMPATHIES 349 









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350 INTRODUCTION TO THE STUDY OF MEDICINE 

Thus, a neuralgia of the trigeminal nerve excites reflexly spas- 
modic contractions of the facial nerve (or, as is said, le tic dou- 
loureux of the face). The excitation starting from a viscus, from 
the biliary or urinary passages, gives rise by reflex action to disturb- 
ances in the muscles concerned in the act of vomiting. 

The excitation may also produce paralysis or inhibitory acts — e. g., 
syncope or sensory disorders — which are especially observed in predis- 
posed subjects — for example, in hysterical subjects — and are ex- 
pressed in their highest degree by a sensitivo-sensorial hemianaes- 
thesia. 

We have already repeatedly shown the frequency of vasomotor 
reactions in distant parts : redness of the cheek in pneumonia, pul- 
monary congestion in hepatic colic, and the vascular spasm of the 
myocardium resulting from excitation of the heart, lung, or stomach, 
and expressed by an attack of angina pectoris. 

Do we need to recall, among secretory disturbances, the salivation 
of gastric affections, the anuria consecutive to abdominal traumatisms, 
the polyuria or oliguria in sciatic neuralgia, according as the pain 
is slight or intense ? We could cite also various general reactions and 
psychical disturbances. In all these cases the manifestations seem 
to have no relation with the organ affected, but are easily explained 
by the mechanism of nervous reactions. 

Eesume. — If we consider in their ensemble the various results 
above recorded, we will understand that a lesion never remains local. 
As soon as a disturbance is produced, it gives rise to secondary mani- 
festations, which become themselves the starting point of reactions 
of a third order, etc. 

Let us take up an illustration to which we have often referred. A 
person has an attack of hepatic colic: the local disturbance causes 
changes in the circulation of the lung; then the heart is influenced, 
and auscultation reveals an exaggeration of the second pulmonary 
sound and a right galloping murmur. The heart may become insuffi- 
cient and dilate; in this manner a little spell of asystole occurs, giv- 
ing rise to new symptoms, notably to oedema in the lower extremities. 

Likewise, it could readily be shown that the kidneys give rise to 
cardiac disturbances, which in their turn influence the lungs, the liver, 
and the kidneys themselves. 

Thus, the phenomena becoming more and more complicated, clin- 
ical types are constituted which are never so simple as might be sup- 
posed from the systematic descriptions found in treatises on pa- 
thology. 

In dealing with a patient, the duty of the physician is, therefore, 
to trace the succession of the various events. Only by an attentive 



FUNCTIONAL SYNERGIES AND MORBID SYMPATHIES 351 

study and minute examination is it possible to reconstitute the mor- 
bid train and recognise which organ has been the starting point of the 
phenomena observed. 

Fever 

The connections which unite the different parts of the organism 
account also for the development of general symptoms in the course 
of the most varied affections. The secretory modifications, the dry- 
ness of the tongue, oliguria, respiratory or cardiac disturbances, nerv- 
ous manifestations, and notably delirium, are to-day easily explained. 
All these symptoms are due to reflex acts, and especially to the im- 
pregnation of the organism with soluble substances. 

The same theory is applicable to the changes produced in thermo- 
genesis. Sometimes, and this is most frequently the case, the tem- 
perature rises; it is then said that there is hyperpyrexia (hyper- 
thermia) or fever; sometimes it falls, that is hypothermia terminat- 
ing in grave cases in algid collapse. 

The expressions hyperthermia and fever are not altogether synony- 
mous. The term hyperthermia means simply elevation of tempera- 
ture. The term fever is applied to a whole series of phenomena of 
which hyperthermia constitutes but one element. It implies the co- 
existence of the thermal elevation with secretory and nervous dis- 
turbances. 

The distinction is somewhat subtle. Of course, we must leave 
aside the hyperthermia produced by a sojourn in the oven. But when 
thermal elevation is of internal origin, the distinction between hyper- 
thermia and fever is difficult to establish. Without dwelling upon this 
question, which would carry us too far, we shall confine ourselves for 
a moment to the consideration of the mechanism of febrile hyper- 
thermia. 

Is fever, according to the old expression, a heat against nature? 
For our part, considering morbid phenomena as identical in their 
essence with normal phenomena, we can not accept such an idea. 
Fever appears to us to be an exaggeration of natural heat; and this 
view is corroborated by numerous facts forming a transition between 
that which might be called physiological fever and that which is des- 
ignated as pathological fever. 

In fact, let us consider the mechanism which explains animal heat 
and accounts for its regulation. It is known that the temperature of 
animals is higher than that of the surrounding medium, because living 
matter, in manifesting its vital activity, renders apparent the heat 
which it had stored up. The muscles and glands thus disengage a 
quantity of heat the more marked as their function is the more active. 



352 INTRODUCTION TO THE STUDY OF MEDICINE 

The digestive canal, as a result of the chemical transformations and 
microbic fermentations taking place in it, also furnishes the organism 
with heat. 

Heat thus produced is dissipated by cutaneous radiation and by 
evaporation on the surface of the skin and certain mucous mem- 
branes, notably of the mouth. 

When the production or the elimination of heat varies, an auto- 
matic mode of regulation intervenes; the nervous system increases or 
diminishes the organic combustions, or, through vasomotor modifica- 
tions, favours or hinders its loss. At the same time soluble substances, 
emanating from the cells and tissues, pass into the blood, and, directly 
or indirectly, through the nervous system, modify the production or 
the dissipation of it. 

However perfect the regulation may be, it may happen, even under 
physiological conditions, that the organism should fail to maintain a 
perfect balance. Therefore transitory thermal rises occur as the 
result of some violent muscular exertion, laborious digestion, painful 
excitation, prolonged intellectual contention, or emotion. At other 
times, hyperthermia results from too energetic a reaction — e. g., an 
individual is suddenly submitted to cold; in order to remedy the loss 
of heat, the organism calls into play too intense reactions, and the 
hypothermia produced by the cold is followed by an exaggerated 
hyperthermia. In order, however, that the nervous system may be 
capable of raising the temperature by reaction, the excitation must 
not be too violent; for, in the latter case, inhibitory acts are pro- 
duced which terminate in coldness and collapse. Nervous shock is 
a well-known illustration of this eventuality. 

If we consider pathology, we see that the different varieties of 
fever may be brought under two pathogenic groups : fever by nervous 
reaction and fever by intoxication. 

We shall not dwell upon the former, which we have repeatedly 
studied. Three varieties of it may be admitted. These are, in the 
first place, the algid fevers, resulting from painful excitation. The 
so-called hepatalgic fever, accompanying hepatic colic when no symp- 
tom points to an infection of the biliary passages, is the best ex- 
ample of such fevers. It has also been experimentally produced 
in the dog by excitation of the biliary passages. We admit also 
reactionary fevers', consecutive to some hypothermizing action — for 
example, an individual has ingested carbolic acid; his central tem- 
perature falls to 35° C, but a few hours later it again rises and 
reaches 39° or 40° C. The third variety comprises the febrile move- 
ments caused by traumatisms bearing upon certain parts of the nerv- 
ous centres; their reality has been demonstrated by a few observa- 



FUNCTIONAL SYNERGIES AND MORBID SYMPATHIES 353 

tions, notably by a case of meningeal hemorrhage recorded by Josue, 
and by experimental researches — for example, those by J. F. Guyon. 
Hysterical fever may be embraced under this variety. 

Fevers of toxic origin are by far the most important. They include 
three varieties. At times febrile movement is consecutive to the 
introduction into the organism of completely formed toxic substances 
proceeding from without. The number of hyperthermizing substances 
is quite restricted; we shall cite strychnine, caffeine, and curare. At 
other times, fever is due to auto-intoxication, and, finally, to microbic 
intoxication. 

The existence of fevers by auto-intoxication has been demonstrated 
by numerous experiments and rigorous clinical observations. With 
this group should be classed the fever of gouty and chlorotic patients, 
the fever consecutive to the absorption of traumatic sanguineous exu- 
dations, and to attrition of tissues, certain forms of fever due to over- 
exertion, and the fever of asphyxia. 

The fevers by microbic intoxication evidently constitute the most 
important class. As all the other infectious manifestations, fever 
depends, not upon the direct action of microbes, but upon the action 
exerted by their soluble products. 

It must be noted, however, that most of the microbic toxines, when 
injected in high doses, instead of raising, lower the temperature ; they 
entail death in algid collapse. This result is important, in the first 
place, because it explains certain clinical facts ; then, because it leads 
to a hypothesis regarding the pathogenesis of fever. It may, in fact, 
be questioned whether toxo-microbic fever is not due to a reaction of 
the organism, whether the soluble products of pathogenic agents do 
not always tend to lower the temperature. If such is the fact, they 
only excite fever as a reaction of a second order, which expresses a 
curative effort of the organism. Accordingly, fever is not directly 
caused by the microbe, but represents, on the contrary, a reaction 
against hypothermizing substances, and should, when not exceeding 
certain limits, be considered as salutary. It expresses, at all events, a 
sufficient energy on the part of the organism, and this view seems per- 
fectly in harmony with facts. One might, in support of this hypoth- 
esis, recall the frequency of chills in the beginning and in the course 
of infectious diseases. Chills represent a mode of reaction to which 
the organism resorts when it is cold: it is a means of getting warm. 
Its appearance would therefore be incomprehensible if toxines were 
heat-producing substances. Nothing is simpler, on the contrary, if 
we admit that microbic poisons tend to lower temperature ; the organ- 
ism reacts by chills and by hyperthermia. It is well to note, finally, 
that the gravest and the most rapidly fatal infections lower tempera- 



354 INTRODUCTION TO THE STUDY OF MEDICINE 

ture. This is what occurs in cholera or even in choleralike diarrhoeas ; 
fever is, in this case, of a good diagnosis. Similarly, in most of the 
experimental infections, temperature sinks below the normal when 
precursory symptoms of death appear: at that moment the organism 
gives up the struggle and undergoes, without reacting, the action of 
hypothermizing toxines. 

If it is at present easy to conceive the pathogenesis of fever, it is 
quite difficult to explain its pathological physiology. 

It seems demonstrated that thermal elevation results from an 
augmentation of tissue wasting, but this tissue wasting does not take 
place in a regular way. In fact, it is seen from the researches of Dr. 
A. Robin that if oxidation sometimes increases in simple phlegmasias, 
it always diminishes under typhoid conditions. 

It must therefore be admitted that tissue wasting is vitiated, and 
this is in harmony with all the results that we have thus far reported 
with respect to the chemical and toxic characteristics of the blood 
and urine. 

At the same time that the production of heat is increased, its 
dissipation also seems to be increased. There is, then, exaggeration 
of the two normal processes which assure thermal regulation; if the 
latter is disturbed, it is because production has exceeded dissipation. 

Such is the general idea one may form of fever, or, more exactly, 
of variations in plus or in minus of animal heat. The history of 
thermal variations is certainly one of the most interesting problems 
raised by the study of functional synergies ; it is the most remarkable 
illustration of morbid sympathies. 



CHAPTER XX 

EVOLUTION OF DISEASES 

Evolution of infectious diseases — Incubation : its variations — Invasion — Stationary- 
period — Local and general manifestations — Different types of fevers — Clinical 
forms — Termination of infectious diseases: crises — Convalescence — Relapses — 
Recurrences — Passage of infections from an acute to a chronic state — Death 
in infections — Evolution of noninfectious diseases — Evolution of intoxications 
and visceral infections — Intermittence and periodicity — Latent diseases — Me- 
tastases — Recovery and death in general. 

We have repeatedly seen that disease depends upon two factors, 
namely, the action of a pathogenic cause and reaction of the organism. 
The action is immediate; the reaction may be delayed. Let us con- 
sider, for example, the traumatic agents. The effects of these agents 
are produced instantly — e. g., fracture, dislocation, or hemorrhage is 
observed at once. It has long been recognised, however, that these 
are not instances of disease properly so called, and a distinction has 
justly been made between wounded and diseased individuals. 

Traumatism may, nevertheless, provoke either early or tardy 
reactionary manifestations. Syncope or nervous shock develops so 
rapidly that the interval between action and reaction — i. e., the latent 
period — passes unnoticed. On the other hand, traumatism is the 
point of departure of phenomena of cicatrization which are of more 
tardy appearance. Cellular proliferations are produced, leucocytes in- 
tervene, and thus reparation begins after a certain period of latency. 

In studying the physical agents we observe phenomena quite similar 
to the preceding. Under the influence of a very energetic agent, 
immediate destruction may occur. For example, an ignited mass fall- 
ing upon the integuments at once produces carbonization. At the 
same time instantaneous reactions are observed. Such, for instance, 
are nervous shock or syncope, occurring in individuals falling into 
either icy or boiling water, or who have been shocked by an electric 
current. 

More or less slow reactions are oftener produced by physical 
than by mechanical agents. In cases of sunstroke, erythema does 

355 



356 INTRODUCTION TO THE STUDY OF MEDICINE 

not appear immediately. On the contrary, a certain period of latency 
elapses between the action of the cause and the development of 
symptoms. 

With chemical agents the effects are still slower. Without doubt 
certain caustics immediately produce destruction of the tissues, but 
this is exceptional. In most cases the alterations are slowly produced, 
as is noticed when a cauterant or vesicant is applied to a patient. 

The phenomena are still more striking with toxic substances. If 
we except a few extremely violent poisons, such as prussic acid, quite 
a long time elapses between their introduction and their effects. 

In cases of slow poisoning — i. e., repeated ingestion of small doses 
of a toxic substance — disturbances may not appear until the end 
of several days, months, or even years. The disturbances are mani- 
fested not because the dose has been increased, but because cumulative 
effects and inappreciable deviations from the normal have become 
apparent as the result of summation. 

A period of latency is also observed in acute poisonings. This 
period corresponds to the time required for the absorption and 
passage of the poison through those organs which may annihilate 
it and its arrival at those organs upon which it will exert its 
action. 

In certain instances the phenomena are still more complex. The 
poison, even when directly introduced into the blood, does not act 
immediately. Such, for example, is the case with phosphorus. In 
this instance a secondary auto-intoxication is established. The cells, 
having been disturbed in their function, produce toxic substances which 
give rise to symptoms. In other words, the poison acts in an indirect 
manner. 

This conception, which is as yet merely an hypothesis, has been 
extended to microbic poisons. Courmont maintained that the toxine 
of tetanus modifies the life of the cells, which, acting under its in- 
fluence, produce a convulsive substance. It is true that this theory 
has been severely criticised and is not as yet well established, but it 
is interesting and worthy of note. 

Parasitic causes, of which we must here say a word, are never 
productive of immediate effects. There is always a period of latency 
during which the pathogenic agent develops. It is for this period 
that the term incubation must be reserved. This expression is not 
applicable to other processes; it indicates that multiplication of the 
morbific agents is taking place. 

Thus, when a cause acts upon the organism, two events are pos- 
sible. These are: 

1. Immediate effects are produced, as is nearly always the case 



EVOLUTION OP DISEASES 357 

with mechanical agents, often with physical agents, and sometimes 
with chemical agents, but never with animate agents. 

2. A period of latency exists which is rare with mechanical agents, 
frequent with physical and especially with chemical agents, and con- 
stant with parasitic agents. In the last case, and in this only, the 
period of latency should be designated as incubation. 

In order to avoid confusion by a too general study, let us first 
consider a well-defined group and note in what manner evolution 
occurs in infectious diseases. 

Evolution of Infectious Diseases 

In the evolution of infections, four stages or periods are generally 
admitted. These are: 

Incubation, which corresponds to the development of the patho- 
genic agents. 

Invasion, which indicates the beginning of reaction on the part 
of the organism. 

Stationary period, during which the disease remains stationary, 
presenting only more or less marked oscillations of aggravation or 
amelioration; and 

Decline, which is a rather inconstant period. 

We will now take up the study of each of these periods. 

Incubation. — As already stated, incubation corresponds to the 
time elapsing between the deposition of a morbid germ in the tissue 
and the first appearance of local or general manifestations of the 
disease. 

This definition is applicable only to hetero-infections, and must 
be slightly modified when the process is one of auto-infection. In 
the latter case the germ is not deposited in the organism from without, 
and therefore the stage of incubation begins at the moment when 
the dormant microbe, until then inoffensive, becomes pathogenic under 
the influence of any excitation whatever. It can readily be understood 
that if it is difficult to determine the time of incubation in the former 
case, it is almost impossible to do so in the latter. 

During the period of incubation the organism does not always 
remain passive; on the contrary, it may endeavour to destroy the 
microbes invading it. Should it fail to do this, however, the disease 
becomes manifest. It is therefore incorrect to say that infectious 
disease is a reaction provoked by the introduction of a microbic agent, 
since morbid reaction does not necessarily occur in all cases. The 
microbe may be destroyed or remain quiescent at the point where 
it was deposited. In order that manifestations may appear, a period 
of preparation is required which represents a first defeat of the 



358 INTRODUCTION TO THE STUDY OF MEDICINE 

organism. We are thus led to admit the occurrence of three succes- 
sive stages at the beginning of all infections, namely, introduction 
or exaltation of the microbe; a latent period of development, corre- 
sponding to incubation; and a reaction of the organism correspond- 
ing to invasion — i. e., to the beginning of the disease. 

The period of incubation may be completely in abeyance and de- 
prived of all morbid manifestation. Then, at a given moment, 
reaction is produced, often quite suddenly. Such, for example, is 
the beginning of lobar pneumonia. It is a very curious fact that the 
microbe should be able to continue secreting its toxines in a progressive 
degree without provoking any disturbance on the part of the organism, 
and that the organism should act so tardily when it is, as it were, 
saturated with soluble toxic products. In other instances the be- 
ginning of the disease is manifested in a slow and insidious manner — 
e. g., as occurs in typhoid fever. Then the transition from a normal 
to a morbid condition is so insensibly effected that it is difficult 
to say at what moment the disease commenced. 

Even when the beginning is sudden it is often difficult, if not 
impossible, to determine the time of incubation, since we are not 
always able to decide as to the moment when contagion has taken 
place. Most frequently patients are unable to give any information. 
In the eruptive fevers — e. g., smallpox — it is very rarely possible to 
determine under what conditions contamination has occurred; in the 
majority of instances the disease seems to be spontaneously devel- 
oped. Observations made during three years in the hospital of La 
Porte d'Aubervillier give a total of 2,304 patients attacked with 
eruptive fevers. Minute interrogation showed that contagion could 
be traced in the following proportion: 21 per cent in measles, 12 
per cent in scarlatina, 13 per cent in varicella, and 38 per cent in 
smallpox. Still, the fact remained that, in the majority of the cases, 
the information obtained was lacking in precision; it was impossible 
to determine exactly what day contamination had occurred. Finally, 
in the case of prolonged incubation there is always a question whether 
there has not been an ulterior contamination which has escaped notice. 
Consequently, in order to arrive at incontestable results, a series of 
circumstances that are seldom realized are required. 

The perusal of works published on incubation leads to the con- 
viction that an average duration, varying only within narrow limits, 
exists for the majority of diseases. It would be a grave error, how- 
ever, to overlook the fact that the period of incubation is at times 
shortened and at other times prolonged within considerable limits. 
Nothing in this regard is more demonstrative than the history of 
venereal diseases; for it is in this class of affections that the moment 



EVOLUTION OF DISEASES 359 

of contamination may be determined most exactly and that inter- 
pretation is easiest. 

With syphilis, for example, it is generally from twenty to thirty 
days after infecting intercourse that the chancre appears; this aver- 
age, which is sufficiently wide in its scope, does not, however, include 
those cases in which infection occurs at the end of ten days, nor 
those in which it has been delayed until the fortieth or even fiftieth 
day. The variability of this period is well illustrated by the fact 
that several indurated chancres, resulting from a single infection, 
may appear successively in the same individual at intervals of sev- 
eral days. 

The same variations occur in gonorrhoea. The average is from 
two to five days, but the discharge sometimes commences at the end 
of twenty-four hours or appears very tardily at the end of several 
weeks. In the latter case it is assumed that the microbes deposited 
in the balano-preputial furrow had not invaded the urethra until a 
certain time after coition. 

With the soft chancre incubation is more fixed and does not exceed 
twenty-four hours. This figure is confirmed by numerous inoculations 
practised upon subjects affected with suspicious ulcerations. 

Information is quite precise in cases of infection of traumatic 
origin. 

In the case of tetanus the period of incubation is from two to 
three days; but there are cases on record in which it is said not 
to have exceeded two hours. On the other hand, it has also been 
prolonged to thirty and thirty-five days. 

In hydrophobia the incubation period is still more variable, the 
average being thirty days, and the minimum fourteen. As to the 
maximum, a period of eighteen months has been admitted, although 
there are certain cases in which the period of incubation lasted two, 
three, and even four years. 

Erysipelas may be considered as occupying a position between 
traumatic diseases and those apparently spontaneous. Most of the 
classic treatises fix its period of incubation at three or four days, 
admitting that it may be reduced to two days or prolonged to twelve. 

In order to determine the duration of the period of latency, trau- 
matic cases must be considered. By an examination of 42 observa- 
tions we obtain the following figures : 

Incubation period from 7 to 18 hours 6 cases. 

" " 24 " 5 " 

" from25to72 " 17 " 

" " " 4 to 8 days 10 " 

« " " 10 to 14 " 3 " 

" " 22 " 1 case. 

24 



360 INTRODUCTION TO THE STUDY OF MEDICINE 

In cases of prolonged incubation it may always be questioned 
whether there has not been a second exposure. However, experi- 
mentation inclines us to admit the accuracy of the figures furnished 
by clinical experience. The inoculation of a few drops of a culture 
of streptococcus beneath the skin of the ear of a rabbit is followed by 
the development of erysipelas after the elapse of a period varying 
from a few hours to eleven days. 

The study of nontraumatic diseases yields figures which are far 
more variable. 

Among the eruptive fevers, precise information is most easily 
obtained in smallpox. Its period of incubation is, on an average, 
twelve days, but it may vary between seven and fifteen. 

In scarlatina, Sevestre finds an almost invariable average of four 
to five days; but there are observations recorded in which the period 
of incubation lasted no longer than twenty-four (Trousseau), twelve 
(Sevestre), and even seven hours (Thomas). In other cases it has 
been prolonged to twelve, seventeen, and forty days (Eilliet and 
Barthez). The period of incubation seems to be shorter in surgical 
or puerperal scarlatina, in which it is hardly three days. This is 
probably due to the fact that traumatism lessens the resistance of 
the organism. 

The incubation period of measles is from eight to twelve days, 
with a minimum of four and a maximum of fourteen ; that of rubeola 
is eighteen days; and that of smallpox from thirteen to nineteen 
days, etc. 

Of other infections we may mention diphtheria, which begins from 
two to four days after contagion, and whooping cough, which appears 
from the second to the eighth day. It is stated that cholera has at 
times developed a few hours after contact, and that in typhus the 
attack has occurred even instantly. In such cases individuals 
approach a patient, feel a pain which alarms them, and are immedi- 
ately forced to lie down. 

The table on the opposite page, which indicates the average, maxi- 
mum, and minimum incubation periods, is based upon facts recorded 
by various authorities, upon statistics published by Williams on behalf 
of a London commission, and upon our own personal observations. 

Clinical experience suffices to establish that the duration of the 
incubation period is very variable, and experimental researches have 
demonstrated certain causes which precipitate or delay the beginning 
of a disease. 

Firstly, there is an idea which should never be lost sight of, and 
that is the variability in the action of viruses. Viruses may be divided 
into two groups — namely, fixed and variable. In this regard nothing 



EVOLUTION OF DISEASES 
Incubation 



361 



Anthrax 

Chancre, soft. . . . 

Cholera 

Diphtheria 

Erysipelas 

Glanders 

Gonorrhoea 

Influenza 

Mumps 

Malaria 

Measles 

Pest 

Rabies 

Rubeola 

Scarlatina 

Smallpox 

Sudor anglicus. . 

Syphilis 

Tetanus 

Typhoid (fever).. 

Typhus 

Vaccinia 

Varicella 

Whooping cough 



Average. 



2 days. 

1 to 2 days. 

2 to 4 " 

2 days. 

4 to 6 days. 

3 to 5 " 
3 to 5 " 

3 to 4 " 
15 days. 

6 to 10 days. 
8 to 12 " 

1 to 3 " 
20 to 60 " 

18 days. 

4 to 5 days. 
12 days. 

2 to 3 days. 
20 to 30 " 

2 to 3 " 
14 days. 
12 " 

3 " 

14 to 15 days. 
8 days. 



Minimum. 



1 day. 
1 " 

1 " 

2 days. 
7 hours. 

24 " 
1 (?) 2 days. 

1 day. 
7 days. 

99 hours. 

4 days. 
10 hours. 
13 days. 

5 " 

7 hours. 

7 days. 
24 hours. 
10 days. 

2 hours. 
2 days (?) 

(?) 

13 days. 
2 ' : 



Maximum. 



3 days. 


3 " 


6 " 


15 " 


22 " 


3 months. 


1 to 7 weeks. 


5 days. 


30 " 


Several months. 


14 days. 


4, 6 to 12 (?) days 


18 months. 


21 days. 


7 weeks. 


15 days. 


(?) 


50 days. 


35 " 


21 " 


23 " 



19 



is so instructive as the history of rabies. The variable virus is that 
found in an animal which has accidentally become rabid {rage des rues) ; 
the fixed virus is that which has acquired a definitely determined 
power by virtue of successive passages through animals. By inoculat- 
ing the virus into animals of the same species placed under the same 
conditions, the phenomena are made to appear after the elapse of a 
perfectly determined period of time. Such is not the case, however, in 
Nature, and the constant variations in virulence lead to modifications 
in the incubative period. 

The same result is observed in man. By virtue of its transmission 
by successive inoculations, vaccine has become a fixed virus; its period 
of incubation is well-nigh invariable. In subjects vaccinated for the 
first time the eruption begins seventy-two hours after inoculation, 
and is well developed in the course of the fourth day. Even with this 
fixed virus, however, certain variations are observed. Dr. Saint- Yves 
Menard has kindly furnished us with interesting information upon this 
subject, which is as follows: The incubation period of vaccination 
quite often lasts four to five days, exceptionally six or seven. In this 
respect the following is a very curious result: Children are returned 
seven days after vaccination with a negative result ; they are vaccinated 
a second time, and in certain exceptional cases the first punctures as 
well as the second will be seen to be followed by the simultaneous 
development of pustules eleven days after the first inoculation. It 



362 INTRODUCTION TO THE STUDY OF MEDICINE 

is thus seen that the vaccine virus is but slowly destroyed, and if 
the organism be profoundly modified by a new inoculation, such will 
suffice to cause the development of germs which seemed to have been 
destroyed. 

The soft chancre, which is transmitted by direct inoculation, has 
also acquired a sufficiently fixed power, exactly as in the case of ex- 
perimental virus. Therefore the lesion always begins to make its 
appearance twenty-four to forty-eight hours after infection. The 
occurrence of a longer period of incubation must be attributed to 
inaccurate observation. 

It can readily be understood that with viruses of variable potency 
the incubation period will be the shorter the greater the energy and 
number of microbes introduced. 

The period of incubation will also vary with the location of the 
wound. It will be longer if the affected region is provided with a 
dense cellular tissue and is poorly supplied with vessels and nerves. 
Such is strikingly the case in rabies. 

Finally, microbes develop more readily when they are introduced 
simultaneously with agents favouring their multiplication, such as 
irritating substances or other bacteria, even though the latter be 
simple saprophytes. 

As to the organism, all causes of weakening should be taken into 
account — extensive traumatism, laceration of tissues, modifications of 
the general condition by overexertion, excesses, alcoholism, intoxica- 
tions, and previous and present diseases. Lastly, we must not over- 
look the influence of moral impressions, whose power is well known 
with respect to rabies. For example, an individual who has been 
bitten by a rabid animal no longer thinks of his accident. All at 
once a word reminds him of the bite, and immediately manifestations 
of rabies appear and rapidly end in death. 

The duration of the period of incubation may also be modified 
by the responsive aptitudes of the subject. In persons with very 
sensitive nervous systems, the onset will be hastened. In this par- 
ticular case a short incubation period constitutes a favourable phe- 
nomenon. 

Invasion. — Invasion may be sudden, or slow and progressive. In 
the former instance the stationary period is quickly reached; in the 
latter it supervenes only at the end of a few days, and is thus pre- 
ceded by a prodromic period in which the symptoms are inadequate 
to determine the nature of the morbid process. 

As an example of infection with sudden onset, writers always cite 
pneumonia, and as an example of slow invasion, typhoid fever. These 
two illustrations are well chosen. Clinical phenomena are always so 



EVOLUTION OF DISEASES 363 

variable, however, that exceptions may be mentioned. There are 
cases of pneumonia beginning in a slow and insidious manner, as 
often occurs in the aged ; and there are typhoid fevers which are mani- 
fested by a sudden onset, as is sometimes the case in children. 

It is not difficult to understand how a progressive invasion is 
effected. The noxious substances are secreted little by little by the 
microbes, become diffused in the organism and influence the cells; 
when the toxines are produced in greater amount, their constantly 
increasing accumulation gives rise to more and more marked dis- 
turbances. 

A sudden onset is more difficult to explain. Even in pneumonia 
it is possible that the morbid poison is secreted in a progressive man- 
ner, and at first sight the sudden appearance of the phenomena is 
not understood. The differences are probably due to the mode of 
action of poisons. This view is, of course, purely hypothetical, but 
it is supported by some facts. A first result which must be taken 
into account is that most microbic toxines, like the poisons properly 
so called, and notably alkaloids, exert no immediate action. Even 
when they are introduced into the blood no immediate symptom is 
produced, but after a period of latency of varying duration the 
morbid phenomena suddenly appear. This experimental result has 
a very important bearing upon our subject. In fact, it may be assumed 
that in certain cases microbic poisons act early and rapidly as they 
are formed. Under such conditions, disturbances begin slowly and 
follow a progressive course. In other instances an oversaturation 
of the organism will be required in order for reaction to be produced. 
This is the first effect of cumulative doses. 

Whatever be the mode of invasion, the general phenomena first 
bear on the nervous system. If invasion is slow and progressive, the 
disturbances are accentuated little by little. These are malaise, head- 
ache, dizziness, weakness of the extremities, and incapacity for all 
muscular or mental exertion. Delirium, if present, is of the mild, 
quiet type. Sleep is disturbed only by nightmares or vagaries. On 
the whole, the symptoms are not intense, but are established gradually 
and aggravated in a slow and often regular manner. 

On the other hand, if invasion is sudden, the nervous symptoms 
will be intense and disquieting from the first. In fact, the pro- 
cess is of the nature of a true outbreak. These has been a silent 
accumulation of toxines, and all of a sudden a violent, impetuous, un- 
expected reaction occurs — i. e., intense chills or, in children, a con- 
vulsive attack. At the same time fever develops and rapidly reaches 
39° or 40° C. Headache is intense, and delirium may be excessive 
from the first. Severe delirious phenomena are mostly, we might say 



364 INTRODUCTION TO THE STUDY OF MEDICINE 

nearly always, observed in diseases characterized by sudden onset and 
occurring in predisposed individuals. Delirium tremens is altogether 
exceptional in typhoid fever; it is not so rare in smallpox and ery- 
sipelas, but it is especially frequent in pneumonia. It expresses a 
profound nervous perturbation, and occurs in alcoholic subjects as 
the result of a toxomicrobic shock — such, for instance, as is induced 
by violent traumatism. 

Likewise, in diseases characterized by sudden invasion, a series 
of symptoms which might, perhaps, be connected with visceral lesions, 
but which seem to be dependent upon a disturbance of innervation, is 
observed from the very beginning. These are, vomiting without any 
apparent alteration of the stomach; diminution in the quantity of 
urine, at times transitory suppression, without the kidneys as yet 
being affected; intense dyspnoea, unexplained by the condition of 
the lungs; acceleration of the pulse, and arrhythmia, which are in 
nowise dependent upon cardiac lesions. There is a striking discord 
between the functional and the anatomical conditions. 

Thus far we have considered only the general symptoms. The 
local manifestations may appear from the beginning; at times they 
precede the general reactions, sometimes they accompany them, and 
sometimes they run their course without giving rise to any general 
phenomena. 

In most cases the local lesions present a course which, even when 
rapid, is generally progressive. In cases of phlegmon or erysipelas, 
as well as in those of pneumonia, it is possible by means of inspection 
or auscultation to follow the extension of the process. 

Sometimes, however, the local lesion develops almost instantly. 
This occurs in young subjects endowed with a nervous system react- 
ing quickly and energetically. Such, for instance, is observed in 
children in conditions described by clinicians as acute pulmonary con- 
gestion. The child is suddenly seized with fever, and auscultation 
practised immediately reveals an intense blowing murmur. On the 
following day everything is again all right; the fever has subsided, 
the murmur is no longer perceptible. These facts, which have been 
so well studied by Bergeron, Cadet de Gassicourt, and Hirne, must 
at the present day be considered as examples of veritable abortive 
pneumonias. Immediately upon its arrival the microbe gives rise 
to violent reactions, which often result in the instant arrest of its 
course. The excitation of the nervous system is expressed by a con- 
gestive fluxion which arrests the infection. In the same order of 
ideas, although their meaning is more difficult to understand, we 
may mention herpes, which is so frequently observed in infections, and 
urticaria, which appears especially in cases of digestive disorders. 



EVOLUTION OF DISEASES 365 

Evidently the phenomena of fluxion are alone capable of making a 
sudden appearance; the other reactionary symptoms develop more 
slowly, and if at times they appear suddenly it is because their be- 
ginning has been effected in a gradual manner, and, having already 
advanced to a certain degree, they become manifest only when they 
abruptly provoke morbid reactions. 

There is often a lack of harmony between general and local mani- 
festations. In a certain number of cases the two orders of symptoms 
begin simultaneously and manifest the same mode of invasion; in 
others the disease is at first characterized by one or the other series 
of symptoms; in still other instances local reactions are progressive, 
while general manifestations are abrupt, and vice versa. There exist, 
therefore, a whole series of different modes of action of which clinical 
experience furnishes well-known examples. 

Stationary Period. — Since the time of Hippocrates it has been 
the custom to admit three periods or stages in the evolution of acute 
diseases: an invading period, a stationary period, and a period of 
decline. Jaumes has proposed another division. He admits but two 
periods — namely, one characterized by a morbid effort corresponding 
to the period in which the organism appears to be overwhelmed; and 
one occurring only in favourable cases — i. e., a period of improvement 
and restoration. In other words, the first period corresponds to the 
attack by the pathogenic cause, and the second to the curative effort 
of the organism. This division is quite in harmony with the present- 
day conception of disease. It would have been perfect if reaction 
really followed action, and if disease followed a regularly descending 
course after arriving at its height through a progressive aggravation. 
In reality the facts are more complex. As we have repeatedly stated, 
the defensive reactions begin at the same time as the offensive actions, 
and at times even before all appreciable symptoms. Consequently, the 
two classes of symptoms constantly intermingle, with the exception, 
however, that the pathogenic agent has the advantage in the begin- 
ning. The reactions of the invasion period indicate that the organism 
is defeated, or at least on the defensive. Then comes a period when 
the struggle assumes a serious character, and the two participants 
fully display their forces. This is the stationary period, which at 
times seems to remain unchanged, and at others to present a series 
of deviations depending upon the various vicissitudes of the struggle. 
This period is the most important from a nosological standpoint, 
since the characteristic symptoms of the disease are well developed; 
they are so grouped as to constitute a special type, which is easily 
defined and classified. It is at this time that a previously hesitating 
diagnosis may be made more certain. 



366 INTRODUCTION TO THE STUDY OF MEDICINE 

In studying the stationary period, the local symptoms and general 
phenomena must likewise be taken into consideration. 

When the local manifestations occupy the external parts, they 
may easily be studied. Such is the case with erysipelas, abscesses 
and phlegmons, cutaneous ulcerations, and gangrene. These also are 
quite easily recognised when they occupy a mucous membrane which 
can be readily explored, such as that of the mouth and pharynx. In 
case a deeply seated organ is attacked, the study becomes more dif- 
ficult; yet, according to the modifications manifested in the functions 
of the organ and the changes which may be perceived by means of 
physical examination, palpation, percussion, and auscultation, we can 
quite exactly determine and follow the evolution of the phenomena 
produced in the deeper parts of the economy. 

In certain instances even the minutest examination fails to reveal 
any organic alteration, because the symptoms are of a general char- 
acter. The latter consist in reactionary manifestations referable 
chiefly to the nervous system, the secretions, and thermogenesis. 

The nervous symptoms are those which have already been noted 
in treating of the invasion period — namely, headache, incapacity for 
work, a diminution of psychical acuity, delirium, and, exceptionally, 
convulsions. The secretions are for the most part diminished; the 
urine is scarce, the saliva is not abundant, and the tongue is dry. 
Finally, thermogenesis is also perverted, and there is usually a rise 
of both peripheral and central temperature. 

A comparison of local and general symptoms leads to the follow- 
ing conclusions : 

Sometimes the local and general phenomena follow a parallel 
course. They are aggravated or diminished simultaneously; they de- 
cline and disappear almost at the same time. Sometimes there is a 
decided discord between the two orders of manifestations. Thus, for 
instance, the local lesion may subside, while the general symptoms 
grow worse. In such cases there is generally some fresh complication. 
More frequently the reverse is the case, the general phenomena van- 
ish, whereas the local manifestations seem to remain stationary. This 
fact is particularly striking in pneumonia. From one day to the next 
a sudden defervescence occurs; the temperature, which had risen to 
40° C, falls to 37° C; the secretions are re-established; the patient 
experiences a feeling of well-being which makes him realize that his 
sickness is over, and yet no improvement has taken place in the con- 
dition of the lung; on the contrary, the stethoscopic signs are the 
same as the day before. The same lack of parallelism is observed 
in erysipelas, but not constantly; the general phenomena subside^ 
while the cutaneous lesion persists without any change. 



EVOLUTION OF DISEASES 367 

Finally, in certain cases the discord is no longer real, as in the 
preceding examples, but only apparent. The local lesion seems to 
remain stationary, and yet the general phenomena are modified or 
aggravated. These indicate either a local change, which we are thus 
permitted to recognise and predict, or a new perturbation, perhaps 
a commencing complication. 

In order to recognise the nature, follow the evolution, establish 
the prognosis, and predict the possible accidents of a disease, we 
must at the same time note its local and general manifestations, and 
their harmony or discordance. 

Let us first consider the local phenomena. Five results are pos- 
sible : 

1. The local lesion, which has begun during the period of invasion, 
is not modified during the stationary period, but follows a very 
simple course, increases gradually, reaches its height, and then, in 
favourable cases, declines. But no notable change in its character or 
aspect appears. 

Of numerous illustrations it will suffice to mention mumps, ery- 
sipelas, and gonorrhoea. We might add scarlet fever and measles, in 
which the eruption characterizing the stationary period extends pro- 
gressively to all parts of the skin, but always preserves an invariable 
aspect. 

2. In other cases the local lesion is modified from day to day. As 
an example in which observation is easy, an abscess may be taken. At 
first induration is found, then the lesion undergoes softening, be- 
comes fluctuating, and opens exteriorly. A like course may be ob- 
served in cases of visceropathies. In simple bronchitis there is a 
period of crudity when expectoration is difficult and painful; then 
a period of coction, when the sputa become mucopurulent and are 
easily thrown out. Examination of the sputa, as well as auscultation, 
demonstrate the changes characterizing these two periods. By the 
same methods of exploration we can follow perfectly the evolution of 
a pneumonic focus: In the beginning there is pulmonary obstruction 
resulting from the exudations, and auscultation reveals crepitant rales ; 
next, a fibrinous exudation into the air cells takes place — this is the 
period of red hepatization, characterized by tubal breathing; finally, 
the exudation softens and auscultation reveals rales of resolution 
(rales de retour). 

3. Instead of remaining localized, the local lesion extends and 
invades the neighbouring parts. Here erysipelas and pneumonia may 
again serve as examples. 

While often circumscribed, erysipelatous inflammation sometimes 
extends to a great part of the skin. At times it covers the entire 



368 INTRODUCTION TO THE STUDY OF MEDICINE 

surface of the body. This is a particular clinical form justly de- 
scribed under the name ambulatory erysipelas. The same evolution 
may be observed in the lung, under which circumstances pneumonia 
is designated as migrating. 

In certain but fortunately very rare cases a local lesion grows 
both deeper and larger, causing considerable loss of substance. This 
is what constitutes phagedenism, observed mainly in the soft chancre, 
which lesion may destroy the penis, invade the scrotum and thighs, 
and follow a serpiginous, extensive course, the duration of which may 
be months or even years. 

4. The local lesion sometimes progresses by successive stages. 
At a moment when the lesion seemed on the point of subsiding or had 
even disappeared, a renewal sometimes occurs in the region primarily 
attacked. This is observed especially in erysipelas. At times the 
renewal occurs in parts more or less distant from the region primarily 
affected — for example, the orchitis occurring in mumps, and endo- 
carditis, pericarditis, or meningitis of pneumonia. The pathogenic 
agent thus tends to colonize distant tissues or organs : it is, as it 
were, a relapse at a distance. 

5. Finally, the local lesion may be modified by an additional infec- 
tion. Pathogenic microbes implanting themselves, for example, in a 
part already diseased, give rise to suppuration, and may even invade 
the economy. In gonorrhoea the gonococcus remains localized in the 
urethra; common bacteria, however, soon join it, and may subse- 
quently provoke very serious disturbances. Although the gonococcus 
may sometimes invade the organism, the so-called gonorrhceal rheu- 
matism nearly always depends upon ordinary pyogenic bacteria. The 
process is one of attenuated purulent infection, to which the agent of 
gonorrhoea has merely opened the way. 

General phenomena usually follow a course parallel to that of local 
manifestations. During the stationary period they may remain quite 
unmodified. In pneumonia, for instance, the fever remains about 
40° C. Dyspnoea, thirst, and headache remain about the same during 
the entire evolution. The same remarks are true of typhoid fever, 
although some differences are revealed by a more careful study. 

In some cases the general symptoms are modified several times, 
so that the stationary period permits of division into a certain number 
of secondary periods. In other instances the general symptoms keep 
pace with the local, as is observed in smallpox. 

Sometimes the changes do not seem to harmonize. Thus, in tu- 
bercular meningitis three periods, which apparently do not correspond 
to anatomical changes, have been described according to the general 
symptoms. After a phase characterized by violent headache, fever, 



EVOLUTION OF DISEASES 369 

constipation, and vomiting, a marked remission occurs, which lasts 
nearly a week; the patient is believed to be convalescent, when the 
symptoms are renewed, and go from bad to worse, ending in death. 

In a certain number of infections the modifications in the general 
symptoms express the generalization of a primarily local microbic 
process. Such is the case with the malignant pustule. The lesion 
is at first characterized simply by a cutaneous eschar; thus, in certain 
cases, phenomena of general infection are subsequently produced, indi- 
cating the invasion of the economy by the pathogenic agent. Like- 
wise, in cases of septicaemia or pyaemia consecutive to local lesions, the 
changes occurring in the general symptoms reveal the invasion of the 
organism. 

Nosologists have divided the stationary period of diseases by tak- 
ing into account both the modifications occurring in the local symp- 
toms and the general manifestations. Undoubtedly, these divisions 
are not always perfect. Didactic descriptions are necessarily sche- 
matic and can not give an exact idea of the complexity of clinical phe- 
nomena. We have above referred to tubercular meningitis. Its evolu- 
tion in three phases, admitted by all the classical treatises, is, how- 
ever, quite rare. The phenomena very seldom, if ever, progress with 
such quasi-mathematical precision as has been attributed to them. 
The clinical types are, in reality, far more complex and variable than 
may be supposed from the classical descriptions. 

Notwithstanding their variability, general phenomena evolve ac- 
cording to four types. Types have been divided into continued, re- 
mittent, intermittent, and irregular, mainly upon the basis of the 
precise data of medical thermometry. 

The continued type is represented by the cases in which the symp- 
toms, after having reached the stationary period, do not present any 
change from one day or one moment to another; the condition re- 
mains the same. The classical example is typhoid fever, which dis- 
ease is often called continued fever. However, on looking into the 
matter more closely, it may readily be recognised that the continuity 
is not perfect; a series of variations is constantly produced which 
have rightly led clinicians to look upon the so-called continued fevers 
as remittent fevers. Every morning the temperature is a few tenths 
of a degree lower than on the previous evening, and the general 
manifestations, although continuing grave, are slightly attenuated. 
These variations are nothing else than an exaggeration of normal 
phenomena. In fact, in health the temperature is modified at dif- 
ferent hours of the day ; it describes a regular curve, whose minimum 
is between 3 and 5 a. m., and maximum between 4 and 7 p. m. ; the 
difference between the two figures is, on an average, 0.8° C. In 



370 INTRODUCTION TO THE STUDY OF MEDICINE 

typhoid fever, the morning temperature usually varies between 39.5° 
and 40° C. ; that of the evening, between 40° and 41° C, the difference 
being from half a degree to one and a half. But it may sometimes 
become more notable. Later on the remissions are accentuated, as is 
observed at the end of the disease. Quite frequently there will even 
be seen at this period great variations tending to bring the morning 
temperature to a normal. This is what is called the amphibolic stage. 

When the remissions become considerable the temperature at cer- 
tain moments returns to the normal figure. The fever is then called 
intermittent. 

The intermittent fevers are often divided into two great groups: 
the malarial intermittent fever and the symptomatic intermittent 
fevers. 

Paludal fever, or malaria, is intermittent because, it is said, the 
parasite which causes it — Laveran's hematozoon — periodically invades 
the blood of those affected; the symptoms then become manifest, 
and are characterized by the three classical stages of chills, fever, and 
sweats. The parasite then takes refuge in certain organs — in the 
spleen and in the marrow of bones — and then the febrile paroxysm 
subsides. The fever will reappear upon a new incursion of the para- 
site. This theory is doubtless too simple, since the parasites are 
often found in great numbers in the blood after the end of the parox- 
ysm. This pathogenesis has been easily admitted for the reason, 
perhaps, that it is difficult to formulate another, perhaps also by 
analogy with recurrent fever. In the latter case, the presence of 
spirilla in the blood exactly coincides with the development of the 
paroxysm. 

The symptomatic intermittent fevers differ from the malarial in 
that their paroxysms are less regular. Contrary to what occurs in 
malaria, the fever generally returns in the evening, is sometimes re- 
peatedly reproduced during the same day, and reappears at different 
hours on the day following. These paroxysms should always arouse 
the suspicion of a suppurating focus in the viscera. They are par- 
ticularly frequent in suppurative hepatitis, angiocholitis, urinary in- 
fections, and ulcerating endocarditis, and almost constant in purulent 
infection. Despite their intermittent course, they are connected with 
progressively growing lesions; they are intermittent, although the 
evolution is continuous. 

This discordance is difficult to explain. It may be supposed, how- 
ever, that the toxines liberated by the suppurating focus act only 
after a certain incubation — that there is produced a phenomenon 
similar to that occurring in cases in which an infection begins sud- 
denly. The paroxysm is the result of cumulative doses and the febrile 



EVOLUTION OF DISEASES 371 

reaction is probably connected with elimination of noxious substances ; 
the symptoms reappear when a new accumulation is produced. 

Whatever may be the explanation, febrile intermission is only an 
exaggeration of physiological remission. All fevers are not freely 
intermittent, probably because each paroxysm begins before the pre- 
vious one is terminated; according to this hypothesis, remittent 
fevers should be considered as intermittent. In this way, it is very 
readily understood that on certain days very marked remissions might 
occur even in continuous fevers. This is frequently observed in 
typhoid fever, notably toward the fourteenth day, sometimes the six- 
teenth or the nineteenth. 

Clinical Forms. — The stationary period of infectious diseases, 
being the longest, and especially the best characterized, has served to 
differentiate clinical types. 

On the basis of their evolution, cyclical diseases may be admitted 
in which the duration is sufficiently defined and is determined by a 
regular succession of morbid phenomena. Pneumonia, typhoid fever, 
and eruptive fevers belong to this category. However, it should be 
remembered that the figures given by authorities are subject to numer- 
ous variations. The term of nine days assigned to pneumonia, and 
of three weeks to typhoid fever, represent averages which are seldom 
realized. 

Nevertheless, the term may be retained in contradistinction to 
noncyclical diseases, such as diphtheria or erysipelas, whose capricious 
course defies all efforts at averaging. 

Even in those diseases in which the stationary period is best deter- 
mined, very great variations may be observed. 

In certain cases the evolution is shortened, either because the 
disease assumes a subacute, speedy course, causing death very rapidly, 
or, on the contrary, because it follows an abortive course. Pneumonia 
is again a good illustration. This infection, produced by the classical 
pneumococcus, may kill in certain instances within a few hours. This 
happens in the aged, in diabetics, and in individuals suffering with 
previous diseases, particularly erysipelas. 

In this connection we may also mention the speedy types of scar- 
latina, smallpox, and cholera. Death may occur at the beginning of 
the stationary period, and even before the latter is clearly established. 

Pneumonia also furnishes the best example of an abortive infection. 
The disease begins suddenly, reaches the stationary period, and all at 
once defervescence becomes established toward the third or fourth 
day. Abortive typhoid fevers have also been described, and we may 
also admit the occurrence of abortive fevers — i. e., such as are cut 
short after a prodromic period. Thus, an individual who has been 



372 INTRODUCTION TO THE STUDY OF MEDICINE 

exposed to the contagion of smallpox is seized with all the premoni- 
tory symptoms of this disease ; then the symptoms disappear and the 
eruption is characterized by two small pustules. This is evidently an 
instance of an attack of smallpox deserving the name abortive. Not- 
withstanding the intensity of the symptoms of invasion, the disease 
is cut short. Cases of abortive erysipelas which stop suddenly after 
the period of invasion at the very beginning of the stationary period 
may also be admitted. It is useless to multiply examples. While 
these facts are already well known, we believe them to be far more 
frequent than is usually supposed. Many febrile paroxysms, transi- 
tory malaises, and sudden chills, which are followed by no special 
manifestations whatever, and which run their course in a day and 
sometimes in a few hours, are to be accounted for by an infection that 
is aborted. Consecutive to infections occurring during convalescence 
from eruptive fevers or erysipelas, we often see febrile paroxysms, 
which, it seems, are referable to no other cause. This is demonstrated 
by the fact that numerous transitions are observed between the ephem- 
eral fevers, which can in no wise be accounted for, and those which 
indicate a relapse or a complication. Lastly, the diseases aborting 
spontaneously should be placed parallel with those aborting in conse- 
quence of therapeutic intervention. Cases of this kind, formerly rare, 
will become more and more frequent as we become better acquainted 
with specific medicaments. The latter are sometimes represented by 
vegetable or mineral products. Such are the salts of quinine, which 
arrest the malarial infection; the salts of silver, which stop a begin- 
ning gonorrhoea; and especially the preparations of mercury, which 
suspend the evolution of syphilis. At present specific and abortive 
remedies are looked for in substances derived from immunized ani- 
mals. The results obtained by serotherapy inspire us with the hope 
that the time is not far distant when it will be possible to arrest the 
evolutions of a great number of infectious diseases. 

The acute infectious diseases, even when they follow a cyclic 
course and terminate within a well-determined time, may in some 
cases be prolonged beyond the usual limits. For instance, pneumonia, 
instead of lasting nine days, may not reach defervescence until toward 
the twelfth or even the fifteenth day. Likewise, typhoid and eruptive 
fevers are not infrequently prolonged in an unusual manner, although 
examination of the patient fails to explain the persistence of the 
morbid symptoms. There is, so to say, a torpidity of the organism 
which does not succeed in producing the special conditions capable of 
arresting the infection. 

In a great number of cases, however, prolongation of the disease 
is due to a particular course or to the influence of complications. 



EVOLUTION OF DISEASES 373 

The evolution is prolonged as the result of successive invasions. 
At the moment when the infection is believed to be nearly terminated 
a new focus is produced. Pneumonia and typhoid fever may evolve 
in this manner, and although the new attack is generally of shorter 
duration than the first, the total duration is thereby considerably 
prolonged. This mode of evolution, while rare in the diseases above 
referred to, is the rule in certain infections, such as recurrent typhus 
and intermittent fever. Such is precisely the case with varicella, the 
duration of which is extremely variable on account of the variation 
presented by the course of successive renewals. 

In certain cases the renewal of morbid symptoms is preceded by an 
interval of recovery; then it is said that there is a recurrence. As in 
the case of relapse, recurrence also is generally less grave than the 
first attack; but this rule offers a great number of exceptions. 

Finally, morbid evolution may be prolonged by complications oc- 
curring during the stationary period or convalescence. New phenom- 
ena, mostly due to superadded infections, may thus lengthen the 
duration of a disease for a very long time. 

It is evident that nothing but hypotheses can be advanced as to 
the causes which intervene to abridge or prolong infections. Aside 
from those cases in which secondary complications are produced, it is 
not understood why the morbid action is cut short, and then reappears 
at the moment when defervescence was about to set in, or even after 
the beginning of convalescence. The solution of these problems is 
intimately connected with the study of predisposition, immunity, and 
the mechanism of recovery. If, as is generally admitted, recovery is 
effected by virtue of chemical and dynamic modifications produced 
within the organism ; if it is dependent upon an increase of the germi- 
cidal power of the tissue fluids and upon the phagocytic activity of 
the cells, the duration of the disease will, of course, depend upon the 
rapidity of the organic changes — namely, upon the reactionary power 
of the organism. Eelapses, on the other hand, would be due to an 
insufficiency of reaction. This explanation, however, is inadequate. 
What we desire to know is the conditions which cause the economy to 
react promptly in one case, slowly in another, and incompletely in' a 
third. The question is thus reduced to a problem of a much more 
general nature. We have seen that the various morbid reactions are in 
part dependent upon the nervous system, and in part due to the state 
of general nutrition. They vary notably from one subject to another, 
and this variability is in relation with the hereditary or personal antece- 
dents of the individual, with his special innate characteristics and idio- 
syncrasies ; in other words, with the different causes to which we have 
constantly referred to explain the development and course of diseases. 



374 INTRODUCTION TO THE STUDY OF MEDICINE 

Reactionary differences also explain the differences of termination. 
When reaction is energetic and timely, it succeeds in destroying the 
invading microbes; if slight or slow, it only arrests their progress 
and the process passes into a chronic condition; if too weak or too 
tardy, it fails to save the organism, and the disease terminates fatally. 

These considerations suffice to demonstrate that the same infec- 
tious disease may present varied symptoms and follow an extremely 
variable evolution. Supposing all conditions to be the same as far as 
the microbe is concerned, the influence of the organism makes itself 
constantly felt and contributes to modify the scene. Therefore a cer- 
tain number of clinical forms have been admitted. These divisions 
are evidently quite arbitrary. In order to establish them, the various 
cases encountered have been compared with an habitual average type, 
running its course without the intervention of any unusual influence. 
In this way clinical forms have been grouped under two heads : First, 
according as modifications depend upon some anomaly in the 
course, or in the morbid symptoms, or in localization; or, second, 
according as they are due to the condition of the subject. With some 
variation this division may be applied to all infections. 

In order to fix the ideas, let us consider the two diseases in which 
clinical types are the most numerous and the most varied — i. e., pneu- 
monia and typhoid fever. The two following tables will show how 
clinical forms may be classified; the terms sanctioned by usage are 
clear enough to make description unnecessary. 

Clinical Forms of Pneumonia 
I. Divisions based on the Study op the Disease. 

1. According to the course. 

Abortive pneumonia. 
Speedily fatal pneumonia. 

! Double. 
With successive foci. 
Migrating. 
Infecting pneumonia. 

2. According to the morbid elements or symptoms. 

Inflammatory pneumonia. 
Adynamic pneumonia. 
Ataxic pneumonia. 
Pneumonia with icterus. 
Bilious pneumonia. 

3. According to localization. 

Pneumonia of the base. 
Pneumonia of the apex. 
Central pneumonia. 
Massive pneumonia. 
Pleuro-pneumonia. 



EVOLUTION OF DISEASES 375 

II. Divisions based on the Condition of the Subject. 

1. According to the age. 

Pneumonia of children. 
Pneumonia of the aged. 

2. According to the previous state of health. 

Pneumonia of cachectics. 

Pueumonia of drinkers. 

Pneumonia of the obese. 

Pneumonia of diabetics. 

Pneumonia of bronchitics. 

Pneumonia of the tubercular. 

Pneumonia of those suffering with malaria, etc. 

3. According to the coexistence of another infection. 

Pneumonia of typhoid fever. 

Pneumonia of erysipelas. 

Pneumonia of acute articular rheumatism, etc. 

Pneumonia of influenza. 

Clinical Forms of Typhoid Fever 
I. Divisions based on the Study of the Disease. 

1. According to the course. 

Abortive typhoid fever. 
Prolonged typhoid fever. 
Speedily fatal typhoid fever. 
Typhoid fever with relapses. 

2. According to the morbid elements. 

Mucous typhoid fever. 
Ambulatory typhoid fever. 
Inflammatory typhoid fever. 
Bilious typhoid fever. 
Hemorrhagic typhoid fever. 
Ataxic typhoid fever. 
Adynamic typhoid fever. 
Putrid typhoid fever. 
Hyperpyretic typhoid fever. 
' Sudoral typhoid fever. 

3. According to the localizations. 

-v T » ( Meningeal. 

JNervous forms < _ . , & 
( Spinal. 

Thoracic form. 

Gastric form. 

Icteric form. 

Renal form. 

Cardiac form. 

Septicaemic form. 
25 



376 INTRODUCTION TO THE STUDY OF MEDICINE 

II. Divisions based upon the Condition of the Subject. 

1. According to the age. 

Typhoid fever of children- 
Typhoid fever of the aged. 

2. According to the previous condition of health. 

Typhoid fever of cachetics. 
Typhoid fever of the obese. 
Typhoid fever of drinkers. 
Typhoid fever of the tubercular. 

3. According to the coexistence of another infection. 

Typhoid malaria. 

Laryngo-typhus. 

Pneumo-typhus. 

Termination" of Infectious Diseases 

We have repeatedly shown that the organism is provided with 
means of protection which prevent the penetration and multiplication 
of pathogenic germs. The latter may succeed in invading the econ- 
omy only when the vigilance of the cells is distracted for a moment 
and the humours are altered by some affection. Then the disease 
manifests itself. Modifications in the cellular nutrition are imme- 
diately produced, however, which transform the blood, the humours, 
and the tissues, and make of them culture media nonadapted for the 
pathogenic agent. Now, two results are possible. In some cases the 
changes are produced slowly and progressively; the organism grad- 
ually rids itself of the germs and neutralizes the action of the toxines 
which impregnate it. Defervescence is produced in a slow manner; 
the fever diminishes progressively, by lysis, and the various functions 
consume a more or less long time in returning to their normal condi- 
tion. It is therefore possible to follow the progress of recovery day 
after day. This is what takes place in typhoid fever. 

In other cases, on the contrary, the termination is abrupt and 
sudden, as in pneumonia. It is then said that a crisis has occurred. 

Crises. — From the earliest antiquity it has been noted that certain 
diseases may present sudden changes in their evolution. This is crisis, 
which supervenes when the peccant (corrupt) humour has undergone 
coction; Nature expels it from the body or causes its deposition in 
some part of the organism. The latter result was formerly considered 
fortunate or unfortunate, according as deposition occurred in an organ 
of little importance or indispensable to life. These ideas led Hippoc- 
rates to formulate the following definition: "A crisis in diseases is 
either an exacerbation, a decline, a metaptosis, another affection, or 
the end." 



EVOLUTION OF DISEASES 377 

The crisis, however, did not occur at "undetermined periods; it 
appeared on fixed days, called critical days, which corresponded to 
weeks or half weeks — that is to say, to the fourth, seventh, tenth, 
fourteenth, seventeenth, and twentieth days. The critical days were 
preceded by the indicating days, when an exacerbation of the symp- 
toms was usually observed. It may be added that Hippocrates did not 
regard the critical days as possessing an absolute value; the crisis 
might occur twenty-four hours sooner or later. Galen, on the con- 
trary, attributed to each day an absolute significance. He argued 
that acute diseases did not last more than forty days, and considered 
the crisis as a sudden reversion to health. 

The latter definition has prevailed. At the present day the name 
crisis is reserved for the ensemble of favourable changes occurring 
suddenly in morbid evolution. 

One of these changes is that of the temperature, which in the 
course of one night falls from 40° to 37° C. In some cases the ther- 
mal reduction is excessive. The thermometer marks 36° or 35° C, 
and this hypothermia sometimes occasions disquieting phenomena, 
especially in the aged; it is attended with collapse, and demands in- 
tervention for restoration of heat to the patient. 

With the fall of the fever the secretions are re-established; the 
skin becomes moist and the urine abundant. On the previous day 
the patient may have voided 500 to 600 grammes; after the crisis 
diuresis may reach 2, 3, and even 4 litres. But what is still more 
notable, perhaps, is the feeling of well-being experienced by the sub- 
ject. As the crisis usually occurs during the night, it is surprising to 
find the individual, who was left in a condition of great suffering on 
the previous evening, completely cured on the following morning. 
The local phenomena, however, have not changed. If the case be one 
of pneumonia, the physician finds the same stethoscopic signs as on 
the previous day; if a case of erysipelas, he observes that the cuta- 
neous lesions have not improved. 

Modifications which might lead the inexperienced to error may 
be observed in the circulatory apparatus. On the previous day 
the pulse may have been rapid and weak, but regular; at the mo- 
ment of crisis it becomes strong and slow, but at times irregular 
and unequal. This phenomenon is observed especially in children, 
and probably depends upon a nervous disturbance, which is of no 
grave significance. 

The sudden and profound changes occurring at the moment of 
crisis may occasion new nervous reactions — e. g., convulsions in chil- 
dren and delirium in adults. There are cases on record in which 
a paroxysm of delirium tremens developed at the moment of defer- 



378 INTRODUCTION TO THE STUDY OF MEDICINE 

vescence of a pneumonia. These disturbances, though sometimes 
alarming, are generally without gravity. 

Among other critical manifestations, transitory erythemata, out- 
breaks of urticaria and herpes, sometimes diarrhoea, a bilious attack, 
or epistaxis, may be mentioned. 

Special attention has been devoted to changes presented by the 
blood and urine. 

Dr. Hayem has described a hematic crisis in which the white cor- 
puscles, increased in number during the disease, return to their nor- 
mal number. The red corpuscles have been progressively diminished, 
and at the time of the crisis an activity on the part of the hemato- 
blasts occurs, designed to increase the red globules. 

The urine has been the subject of numerous researches. During 
the disease its quantity progressively diminishes. At the moment 
of the crisis a veritable discharge occurs. The polyuria is very abun- 
dant. The urea, which may have been reduced to 12 or 15 grammes, 
rises to 30 or 40 ; the chlorides, which were represented by 1 or even 
0.8 gramme, reach 10 and 12 grammes. The modifications in the 
amount of chlorides have been attributed to the diet. This opinion is 
inadmissible, for it is contradicted by the abundant discharge at the 
moment of recovery. It is also known that if chlorides or iodides are 
adminstered to pneumonia patients, these substances accumulate in 
the organism and are eliminated only at the time of crisis. Likewise, 
the phosphates and the sulphates increase when defervescence is pro- 
duced, but in less notable proportions. 

The same is also true with regard to those poisons which are nor- 
mally excreted by the urine, they being in great part retained in the 
organism during the disease. During the stationary period the tox- 
icity of the urine progressively diminishes; at the time of crisis it 
is considerably increased, and reaches, or even exceeds, the normal 
figure. It should not be concluded from this result that recovery is 
due to the sudden elimination or to the urotoxic discharge. On the 
contrary, the reverse is true: it is because the patient has recovered 
that crisis has appeared. This is proved by the fact that in certain 
cases the urinary crisis occurs twenty-four hours before, or, what is 
more demonstrative, after recovery. 

Thus the patient, being cured, is capable of rejecting the poisons 
which impregnate his organism, but to which he had already become 
insensible. As to the crisis, it is to be considered simply as an exag- 
geration of normal phenomena. It is established that in a healthy 
man the elimination of autogenous poisons is not effected in a con- 
tinuous manner: the urinary secretion varies from one day to an- 
other; it follows a tertian, less frequently a quartan type. Then, 






EVOLUTION OF DISEASES 379 

even in a normal state of things, accumulations and discharges are 
constantly produced — that is to say, little crises. It is a particular 
example of a general law to which we have frequently referred. "We 
have already shown that there is no uniform movement in nature, 
and that all vital acts are remittent. Starting from this physiological 
fact, we may regard crisis as a natural phenomenon or an exaggera- 
tion of the normal type. 

The infectious diseases ending by crisis are not very numerous. 
Besides pneumonia, which is the type of the kind, we may cite ery- 
sipelas, smallpox, and typhus fever; however, crisis is not so clear in 
all cases, nor is it of constant occurrence. 

There is a disease in which crisis occurs in a reverse direc- 
tion: that is, cholera. In the stationary period the temperature 
is below the normal; at the moment of recovery it rises above 
and sometimes reaches a figure quite notably above the normal. 
Thus, a febrile, reactionary period develops, sometimes attended by 
grave manifestations, which may impart to the patient a typhoid 
aspect. 

Convalescence. — When the morbid process seems to have been 
arrested and recovery obtained, the organism is not yet completely 
restored. There is still a last period termed convalescence. 

The appetite, which had been suppressed during the disease, reap- 
pears, and is often so marked that it is difficult to prevent the patient 
from overeating. The temperature often falls below the normal; 
the figures 36.5° and 36° C. are not infrequent, and may be observed 
for a week or more. 

Emaciation appears or increases, this being probably due to the 
great amount of waste which is eliminated by the different emunc- 
tories, notably through the respiratory apparatus and the kidneys. 
Then, at the end of a few days, the patient grows fat, his weight 
often exceeding that noted before the commencement of the disease, 
and at times he becomes slightly obese. 

The nervous system having been most affected during the sta- 
tionary period, therefore returns more slowly to its normal condition. 
During the first days following recovery, when all the organs are work- 
ing regularly, the nervous system is still disturbed. The individual is 
unable to keep on his feet or walk; if an abrupt movement is at- 
tempted, dizziness and palpitation are experienced. Now and then 
a febrile paroxysm occurs, as, for instance, when he happens to read a 
little too much, or on the occasion of a visit, an emotion, or an act 
of little importance, such as making his toilet; the thermometer 
then marks 38° or 38.5° C. These disturbances, which seem to de- 
pend simply upon a lack of equilibrium of the centres of thermal 



380 INTRODUCTION TO THE STUDY OF MEDICINE 

regulation, and not upon an additional infection, are transitory and 
in no wise disquieting. 

The nervous manifestations of convalescence are sometimes much 
more marked than would be expected in view of the comparatively 
innocent character of the disease. In this regard nothing is more 
instructive than influenza. Even after the slight forms which have 
lasted but a few days, convalescence is very tedious; weakness, 
asthenia, and incapacity for work may persist for weeks or months. 

Finally, some of the symptoms of the stationary period may still 
reappear. A convalescent from typhoid fever will easily have diar- 
rhoea ; a convalescent from a thoracic affection will, upon the slightest 
cause, cough and have pain in the side. 

Evidently the duration of convalescence varies according to the 
nature, type, and gravity of the disease, and also according to the 
age or previous condition of the subject. Aged individuals and those 
who are already weakened require more time to be re-established, and 
they may often have to go to the country or to a warm climate. 

Convalescence may be interrupted by a great number of accidents. 

Besides the nervous fevers already referred to, other causes may 
produce a rise of temperature up to 39° or 40° C. After a day or 
two the temperature again becomes normal. This is often a process 
of abortive relapse; the disease, not well extinguished, has recom- 
menced and has been arrested by means of timely medication or the 
natural defences of the organism. 

In other cases a septicaemia is superadded to the primary disease. 
Some authorities have even maintained that the relapses of typhoid 
fever should be considered as infections of intestinal origin — i. e., 
that the alterations of Peyer's patches, by lessening the means of 
defence, permit the invasion of the economy by the habitual microbes 
of the alimentary canal. 

Febrile paroxysms connected with cutaneous suppurations may also 
be observed; the alterations of the skin, like those just referred to 
in the intestine, permit the pus cocci to produce abscesses or boils. 
At times an infection is produced in other organs; pneumonia oc- 
curring during convalescence from any disease may be taken as an 
example. 

Lastly, in certain cases febrile paroxysms occur, which are ex- 
plained by the aggravation of an antecedent chronic infection. For 
example, in an individual who has suffered for a more or less con- 
siderable period with a torpid (slow) tuberculosis, and then contracts 
the measles, convalescence does not become duly established after this 
intercurrent infection; he remains weak and suffering; he has slight 
fever every night, and emaciates and loses strength; the pulmonary 



EVOLUTION OF DISEASES 381 

lesions extend, and finally they either cause death, or, after a certain 
time, they are arrested and resume their former slow course. 

Relapses and Recurrences. — Convalescence may also be inter- 
rupted by a relapse. 

In certain infectious diseases relapse is the rule. We refer to 
recurrent typhus, and to a particular form of infectious icterus, im- 
properly called WeiPs disease. 

Eelapse is frequent in typhoid fever, influenza, and broncho-pneu- 
monia; it is rare in uncomplicated pneumonia and exceptional in 
other diseases. In most cases it is caused by a fault of the physician 
or of the patient. Alimentation may have been too rapid or too 
abundant; the patient may have got up too soon, or exposed him- 
self to the cold, and especially to fatigue. It is relatively easy to 
treat a disease during the stationary period; but at the moment of 
convalescence the physician is often greatly embarrassed and requires 
much tact and experience. 

Eelapse sometimes manifests itself in a slow and progressive man- 
ner; more often it appears suddenly, even in the case of typhoid 
fever. In this disease the temperature reaches 39° or 40° C. on the 
evening of the first day. In a general way, relapses are less grave 
and of shorter duration than the primary affection; but there are 
many exceptions to this rule, and a relapse may be more prolonged, 
graver, or even fatal. 

A distinction has justly been established between relapse and re- 
currence (recidive). Eelapse means a new beginning of a disease 
without a new infection; recurrence is connected with a new infec- 
tion. In a good many cases the distinction is easy. When a person 
is attacked with typhoid fever or erysipelas after an interval of fifteen 
or twenty years^ such is evidently a case of recurrence ; but when the 
symptoms reappear at an early period, interpretation becomes ex- 
tremely difficult. Some individuals, particularly women, have ery- 
sipelas every month. Is such a case an example of recurrence or of 
relapse? It is impossible to answer, since we do not know what 
period of time is required for the destruction of the germ. 

The present tendency is to increase the importance of relapses at 
the expense of recurrences, and to admit that the microbes remain 
inactive in the organs and tissues, but ever ready to assume the 
offensive upon the slightest occasional cause. Indeed, it has even 
been asserted that in most cases the recurrences of gonorrhoea are but 
relapses; in fact, the gonococcus persists during an almost indefinite 
period in the urethra which it has invaded for the first time. 

Erysipelas and pneumonia belong to the number of diseases which 
seem truly capable of frequent recidives. Eecurrences of measles are 



382 INTRODUCTION TO THE STUDY OF MEDICINE 

quite common; those of typhoid fever, smallpox, and scarlet fever are 
very rare. As to syphilis, recurrence is altogether exceptional; most 
of the cases cited as examples of a second chancre are accounted for 
by a confusion with tertiary lesions of the genitals, which sometimes 
simulate a primary lesion. 

Passage of Acute Infections to a Chronic Condition. — Although 
recovery is the normal termination of infectious diseases, there are 
certain cases in which the evolution is prolonged beyond the usual 
limits. The disease is then said to have become chronic. 

The duration of acute diseases has been arbitrarily fixed at forty 
days : beyond this term chronicity is supposed to be established. 

If the question be considered from a higher standpoint, it will be 
seen that an essential difference between the two processes is fur- 
nished by the study of the evolution. 

Acute disease is a morbid process in a state of modification; each 
day brings about a change which, though often but slightly marked, 
can nevertheless be recognised by a careful examination. It will 
then be noted that the organism is reacting — that is, struggling with 
all its forces to arrest and destroy the morbific cause. It is in revolt 
against the invader. 

In a chronic disease the organism submits to the yoke of the patho- 
genic agent and seems to have no other ambition than to live with 
it; it hardly tries to circumscribe its progress; it abandons itself, 
being incapable of continuing the battle. The reason the condition of 
the patient is not more quickly reduced is that the invader itself 
has become less active and aggressive. Thus a tacit agreement is 
made between the microbe and the organism, and the disease persists, 
undergoing only extremely slow changes. 

Therefore an acute disease is distinguished by a lively, often too 
energetic, reaction; a chronic disease is characterized by the absence, 
insufficiency, or slowness of reaction. 

At times, however, the organism may for a moment recover its 
energy. The result is acute attacks, often occurring without any 
appreciable cause, and at times as the result of exposure to cold, trau- 
matism, or an intercurrent infection. Under such conditions the 
pathogenic microbe makes a fresh attack, with the result that the 
organism shakes off its torpidity. This acute spell may be ill di- 
rected, undisciplined, and precipitate the morbid evolution and thus 
rapidly cause death. In other instances, after having given rise 
to painful symptoms, it will lead the organism to recovery. A 
rebellious gonorrhoea, for example, has been seen to disappear after 
a new acute attack. This is a cure of disease through aggravation of 
disease. 



EVOLUTION OF DISEASES 383 

Medicine has attempted to imitate these natural procedures — for 
example, irritant local applications realize this indication. Koch's 
tuberculine does not act otherwise; it whips, so to say, the torpid 
evolution of chronic tuberculosis. 

An acute process may become chronic without any notable changes 
being produced : it stops at a given moment of its course. This may 
occur at the moment of aggravation as well as at the time of improve- 
ment of the disease. The violent manifestations subside, the reac- 
tions and pains cease, and in certain cases the symptoms are so slight 
that the patient believes himself cured. Illustrations abound; they 
are mostly drawn from cases of nonspecific infections, mainly inflam- 
mations of organs — e. g., enteritis, nephritis, and cystitis — which 
gradually pass into a chronic condition; also various suppurations, 
commonplace or specific; gonorrhceal urethritis, for instance, is thus 
transformed and often persists during an entire lifetime, occasioning 
no disturbance, and unknown even to the patient. 

Finally, of the specific infections we must specially mention tuber- 
culosis, which, after an acute attack, may follow a slow evolution. 

In order to more closely study the evolution of chronic lesions, 
let us consider an abscess situated somewhat profoundly. In its de- 
velopment it produces various disturbances. Then, when it is opened 
to the exterior, the symptoms cease; suppuration, at first very abun- 
dant, diminishes progressively. An early recovery may be expected; 
but at a certain moment the improvement is arrested, and a fistula, 
giving issue to a sero-purulent liquid, is established. There is no 
longer any general or local reaction; without any apparent incon- 
venience the organism supports this lesion, which becomes chronic. 
However, at the moment when chronicity is established the discharge 
undergoes some modifications. It loses its freely purulent character; 
it becomes more serous, more mucous; at the same time, the microbes 
diminish in number and virulence. 

Failure to recover in such instances is often due to the presence 
of a foreign body, a splinter, or a sequestrum in the focus; or else 
there is diseased tissue at the bottom of the fistula. When it is pos- 
sible to intervene and to extirpate or remove this inflammatory thorn, 
the organism triumphs over the bacteria and the lesion heals. Thus 
foreign bodies, although absolutely harmless when they are aseptic, 
maintain an infection which would be cured in their absence; this 
is a remarkable example of pathogenic association. 

In cases of chronic infections, the microbe, although attenuated, 
is not absolutely inoffensive. It seems even that its feeble pathogenic 
potency is in great measure due to some protective power exerted 
by the wall of the morbid focus. Dr. Chauveau has shown that the 



384: INTRODUCTION TO THE STUDY OF MEDICINE 

pus of a seton which produces no disturbance is virulent; if a par- 
ticle of it be inoculated in another point of the economy, disturb- 
ances are caused. The pus was endured only in its old focus. 

In cases of chronic suppuration, fistulae may from time to time 
become occluded; the subjacent focus is then filled with pus and in- 
creases in volume; it becomes painful and gives rise to fever. After 
an artificial or natural opening, the lesion resumes its slow and chronic 
course. In other cases the fistula becomes closed; it appears to be 
healed, as no symptom is any longer apparent. For months or years 
the lesion gives rise to no disturbance whatever ; then the focus, which 
seemed extinguished, is again kindled, and a new attack is produced. 
Such a course is observed especially in osteomyelitis, where a seques- 
trum may provoke very tardy disturbances appearing at considerable 
intervals. 

The microbe had slumbered for years as an absolutely inoffen- 
sive guest; an occasional, often unnoticeable, cause has permitted it 
to regain a little virulence and give rise to inflammatory reactions. 

A similar evolution is sometimes observed after typhoid fever. 
This disease never passes into a chronic state, but the microbe that 
has provoked it may become localized at certain points, notably in the 
bone marrow, and thus call forth a slow inflammation which termi- 
nates, after several months, in a focus of osteomyelitis. Bacterio- 
logical examination demonstrates the presence of Eberth's bacillus 
therein. In his case the acute disease ends in a chronic process quite 
different from what it originally had been. 

We can find by no means less interesting examples in the history 
of ulcers. Under this name are designated losses of substance having 
no tendency toward reparation. 

Ulcers result from very varied lesions which, owing to peculiar 
conditions, have not been able to terminate in recovery. 

Let us consider, for example, the varicose ulcer. A slight infection, 
an abscess, a pustule, a simple abrasion, having induced an infection 
so mild that no symptom is expressed and the existence of which we 
admit simply by induction, is the starting point. Eeparation is not 
effected because the tissues are altered; their nutrition is profoundly 
affected by the varicose condition of the veins ; the skin becomes hard, 
brownish, and sometimes is attacked with eczema. The little lesion 
sufficed to produce a chronic affection in the suffering tissue. 

The same explanation is applicable in ulcerating dermosynovitis. 
This is a trophic lesion provoked by an ordinary cause or a slight 
infection, and it develops and persists because nutrition is profoundly 
disturbed by the nervous lesions. This ulceration is observed espe- 
cially in ataxics. 



EVOLUTION OF DISEASES 385 

The data of clinical experience are confirmed by demonstrating 
that section of sensory nerves hinders considerably the process of 
repair. For example, division of the sciatic nerve in a guinea pig is 
often followed by ulcerations in the foot operated upon. But if care 
be taken to protect the limb by means of a sort of plaster shoe, infec- 
tion is prevented and no nutritive disturbance appears. 

The same is true of ulcers of mucous membranes. A common- 
place lesion, in most cases of an infectious origin, may serve as a 
starting point for an ulcer of the esophagus, duodenum, and espe- 
cially the stomach. Ulcer of the stomach develops in hyperchlorhydric 
dyspeptics; the excess of acid hinders reparation. Filhene has given 
an experimental demonstration of this pathogenesis. Two rabbits 
received considerable doses of arsenic subcutaneously : in one of them 
kept as a control, gastric ulcerations developed ; in the other, to which 
bicarbonate of soda was administered to neutralize the gastric juice, 
no lesion was produced. 

Although the organism plays a very important part in the develop- 
ment of ulcers, we must recognise that the lesion is sometimes de- 
pendent upon the nature of the pathogenic agent, its degree of 
virulence, and the point where it is developed. The ulcerations of 
tuberculosis, glanders, and syphilis and the phagedenic lesions belong 
to this group ; the influence of the organism, without being absolutely 
nil, is in these cases considerably reduced. 

An acute lesion may pass into a chronic state under a form rela- 
tively favourable — namely, induration. In such instances the organism 
was capable of completely destroying the pathogenic agent, but the 
alterations produced were too profound to admit of perfect repara- 
tion. The tissue, instead of returning to its primary condition, is 
replaced by a newly formed fibrous production. This termination 
is observed in superficial lesions, in certain abscesses, and in adenopa- 
thies, but it is particularly important in deeply situated tissues and 
organs. In this manner cicatrices are produced which, when located 
in the mucous membranes, cause deformity and hinder their normal 
action. When the cicatrices occupy such passages as the esophagus 
or the urethra, they result in stricture; in the viscera, such as the 
heart, liver, or kidneys, they produce sclerosis. In these cases the 
chronic process differs completely from the acute. As we have shown 
with reference to scleroses, the process of repair remedies the first 
disturbances, but creates a hindrance to the regular activity of the 
organs. 

The chronic processes, the mechanism of which we have just indi- 
cated, undergo no modification or progress slowly, either toward re- 
covery or toward death. In both cases changes ending in one or 



386 INTRODUCTION TO THE STUDY OF MEDICINE 

the other of these two terminations are produced either in an insidi- 
ous manner, or else the chronic course is interrupted by an acute attack 
which leads to recovery or death, as the case may be, or a third 
alternative leaves the organism in the same condition as before its 
occurrence. 

Death in Infections. — When an acute disease ends in death, the 
fatal termination may occur abruptly, in an unexpected manner, or 
slowly and progressively, preceded by more or less prolonged agony. 
If autopsy is performed, macroscopic or microscopic lesions are some- 
times found ; in other cases the post-mortem examination gives a nega- 
tive result. By taking into account the diverse results which may be 
obtained, the causes of death may be divided into three groups: (1) 
mechanical disorders or barriers; (2) lesions of an important organ; 
(3) general infection or intoxication. 

As a striking example of the mechanism of death by a mechanical 
cause, we may mention diphtheritic laryngitis. The false membrane 
developing in the larynx hinders the passage of air and may cause 
death, partly mechanically, partly through the reflex spasm which 
it excites. Likewise, a phlegmon taking its origin in certain regions 
may, by its size or by the oedema surrounding it, mechanically induce 
a fatal termination. 

In these examples death evidently results from the obstacle created 
by the lesions, since if the false membrane be detached or the circula- 
tion of air be re-established through intubation or tracheotomy, or 
the phlegmon be opened, the disturbances disappear immediately. 

The local lesion which may thus endanger life is not, however, the 
work of a microbe, but is due to a reaction of the organism which seems 
to fight against itself. If we more closely investigate the succession of 
the phenomena, we understand that the organism has produced a 
false membrane or a purulent focus in order to prevent general infec- 
tion. The lesion thus created was designed to circumscribe the morbid 
process and to oppose the penetration of microbes or their toxines. 
However, the organism is not always capable of proportioning its effort 
to the work required. In a good many instances reaction exceeds the 
end. A microbe penetrating into the lung induces an acute pulmo- 
nary congestion: the vessels dilate in order to facilitate the escape of 
fluids and cells which will arrest the development of the parasite. 
But the reactionary phenomena are often too intense, and may give 
rise to grave symptoms. In other cases, the microbe reaches the sur- 
face of the lung and irritates the pleura, which then secretes a fluid, 
which is often so excessive in amount that evacuation of the exudate 
becomes necessary. 

Lastly, in certain cases reaction is not too strong; it is truly bene- 



EVOLUTION OF DISEASES - 387 

ficial, but it is produced in particularly delicate localities and on that 
account may become dangerous. Such, for example, are congestion, 
oedema, and abscess observed in the brain. 

Under these various conditions the organism has endeavoured to 
remedy the immediate disturbances, but it has mobilized too great a 
number of cells or given issue to an excessive quantity of liquid. 

Therefore, under such circumstances, the necessity of employing 
therapeutic measures to the organism itself with a view of moderating 
the morbid reaction and of endeavouring, for example, to check the 
active congestion, which threatens to give rise to asphyxia by reason of 
its intensity, is of the greatest importance. At other times, on the 
contrary, the organism must be aided in its efforts to accomplish that 
part of its work which it is unable to do alone. Puncture of a pleural 
collection or the evacuation of a cerebral labseess is not medication 
against nature, but a complementary method aiding the insufficiency 
of natural means. 

As, on the other hand, morbid reactions may endanger life by their 
excessive intensity, on the other their insufficiency may be a new cause 
of disorders. When a microbe develops, it gives rise to the local devel- 
opment of deadly substances which destroy the surrounding cells; the 
destroyed elements are liquefied and, when possible, thrown out. When 
the organism fails to remedy the imminent accidents by the various 
means at its disposal, notably through the accumulation of wander- 
ing cells, or if the leucocytes be killed as they arrive at the point of 
invasion, a more or less complete destruction of the affected tissue 
will result. Gradually extending, necrobiosis may reach a vessel, and, 
if the course of the process is rapid, a grave or fatal hemorrhage 
occurs before a clot is formed. In other cases an important cavity is 
opened; for instance, the wall of the intestine is perforated. 

In these various cases lesions which are apparently sufficient to 
account for death will be found at the autopsy. 

As a result of anatomico-pathological discoveries we have become 
so accustomed to attach an exaggerated importance to anatomical 
lesions that we are satisfied when the autopsy reveals a morbid focus 
in some important organ. Let us take, for example, the case of a 
child dead of measles. During life a murmur was found at the base 
of one lung, and, on opening the cadaver, a focus of broncho-pneu- 
monia is, in fact, discovered at that point. The mechanism of death 
in this instance appears to be easily understood. Yet, on a little 
reflection, it will be acknowledged that it is hardly possible to attrib- 
ute the fatal termination to a lesion so small as not to hinder hema- 
tosis to any great degree. The same reasoning is applicable to 
other organs, as well as to those cases in which multiple lesions are 



388 INTRODUCTION TO THE STUDY OF MEDICINE 

found. In acute miliary tuberculosis, when the tubercles have invaded 
the serous system only, why has the individual died? Pushing the 
question further, it must be asked, Why has he succumbed, even when 
the multiple granules have invaded the viscera? There generally re- 
mains sufficient intact parenchyma to assure the function of the organ. 
Without wishing to abuse examples, we may refer to cerebral soften- 
ing, which, even when limited, may occasion death, whereas it is pos- 
sible to experimentally remove the greater portion of the brain with- 
out endangering life. 

The anatomical lesion is a small matter, and it is not sufficient to 
explain everything. 

It is here that modern science intervenes and rightly proclaims 
the role of toxines secreted in the diseased organs and leads to the 
admission that death is due to poisoning. This interpretation is con- 
firmed by those cases in which no manifest lesions are revealed by 
post-mortem examination. 

Let us suppose an individual succumbing to anthrax. The blood 
is disintegrated, dark, and sticky, and the spleen is swollen and the 
other viscera congested. At times small visceral ecchymoses are met 
with, and that is all. This is evidently somewhat disappointing. How- 
ever, on examining a drop of the blood or a particle of the organs 
under the microscope, innumerable bacilli are observed, and thus some 
light is thrown on the problem. Here death is attributable to a gen- 
eral infection — Toussaint said it was due to an obstruction of the 
capillaries by the bacteria. However, this invasion and dissemina- 
tion of the foreign elements does not seem to be sufficient to explain 
the fatal termination. It is neither by crowding the vessels nor by 
abstraction of oxygen or of the materials necessary for cellular reno- 
vation that the bacteria have destroyed life. On the contrary, it is by 
the secretion of soluble substances that the function of the cells has 
been disturbed. 

This interpretation, which may seem contestable as regards anthrax, 
is the only one admissible in reference to those diseases whose patho- 
genic agent is localized at a certain point of the organism. In diph- 
theria, gaseous gangrene, and cholera the microbes do not invade the 
economy ; they remain localized in the skin or confined to the digestive 
canal. Death can not, therefore, be attributed to any other cause than 
the soluble substances engendered by the micro-organisms. 

It is not enough, however, to say that death is the result of an 
intoxication; we will endeavour to indicate the mechanism of a fatal 
termination a little more precisely. 

In certain cases lesions are found which of themselves would be 
sufficient to endanger life. For example, the autopsy reveals degen- 



EVOLUTION OF DISEASES 389 

eration of the liver and kidneys, myocarditis, or hemorrhages of the 
suprarenal capsules; chemical analysis shows the diminution or. even 
the absence of glycogen in the liver; and microscopical examination 
demonstrates cellular lesions in most of the organs. It may then be 
asked whether these multiform alterations have not played a part in 
bringing about the final result, and whether the auto-intoxication re- 
sulting from organic insufficiency has not been added to the microbic 
intoxication. This, however, would tend to again displace the problem, 
for it is at any rate to be recognised that the cellular lesions are in 
certain cases too limited to have exerted a marked influence. 

We are thus brought to again admit a toxic action. This action, 
however, is not immediate; the poisons do not kill rapidly, but a cer- 
tain length of time elapses between the moment of their introduction 
and the instant when the first responsive manifestations appear. In- 
stead of at once arresting the nutritive activity which essentially char- 
acterizes life, and microbic toxines disturb nutrition by adulterating 
the intercellular medium. Whether the poison itself modifies this me- 
dium, or whether the secondary products originating under the influ- 
ence of the toxine act as a ferment, is a matter of little importance. 
What is an important fact, however, and one to be kept well in mind, 
is that even when a fatal dose is at once introduced into a vein the 
animal succumbs only after the elapse of several hours. This means 
that a whole series of modifications in nutrition are produced through 
the influence of the toxine. 

We are thus led to consider not the total death, but the individual 
death of the parts of the organism — i. e., of the cells. It might be 
supposed that, under the influence of toxines, nutrition is equally per- 
verted in all parts of the organism; but such a conception is hardly 
admissible. The cells are disturbed according to a fairly determined 
order — those which perform the highest functions are affected first. 
Since the nerve cells occupy the highest position, experimentation in 
accordance with clinical facts shows that it is upon them that the 
deleterious action of toxines is in most cases exerted. The dynamic 
state of the nerve cells being thus modified, it is comprehensible that 
an occasional cause, by producing in them an abnormal excitation, 
may induce sudden or speedy death. Otherwise, the fatal termination 
supervenes gradually, as the result of a progressive weakening of me- 
tabolism. 

In order to admit these different conceptions without reservation, 
we should be exactly informed as to the functional state of the dif- 
ferent parts of the organism at the moment of death. Here is a most 
difficult question which has not as yet been the subject of experi- 
mental studies. 



390 INTRODUCTION TO THE STUDY OF MEDICINE 

In brief, death as a result of infection is death from intoxication. 
The microbic poisons accumulate in the organism and hinder or pre- 
vent normal cellular life. It is possible that they act by forming com- 
binations with the cellular protoplasm. It is more probable, however, 
that they affect the cells by adulterating the intercellular medium. The 
result is a series of functional disturbances inducing death, and at 
the autopsy no lesion, or almost none, is found even under the micro- 
scope. If any lesions are met with they are too small to explain the 
fatal termination. 

If life is prolonged, functional disturbances induce anatomical 
modifications, and also they secondarily produce important cellular 
lesions which play an important part in the mechanism of deferred 
deaths. Here, however, the question is no longer one of infection, but 
of organic lesions progressing on their own account and deriving no 
particular character from their origin. We are thus led to say a few 
words with regard to the evolution of noninfectious diseases. 

Evolution of Noninfectious Diseases 

It is useless to dwell upon mechanical agents. They do not cause 
diseases, but they produce lesions only. Popular good sense has long 
recognised the distinction between wounded and diseased subjects. 
In the development of wounds we need only study their mode of 
reparation. Traumatism is sometimes a cause of disease, because 
it either excites nervous reactions or opens a door, sometimes to intoxi- 
cation, but generally to infection. It is not necessary to dwell upon 
these facts, which have already been discussed. 

We may also neglect to consider the physical agents, which, as a 
rule, simply produce lesions or some nervous reaction. The role played 
by them has already been pointed out. 

The history of chemical agents — namely, of intoxications — is more 
important. 

Let us first consider acute intoxications. In general, a certain time 
elapses between the moment when the poison is introduced into the 
organism and the instant when disturbances appear. This is the period 
of latency, which must not be designated as incubation, since there is 
no development of a pathogenic agent. Exceptionally, disturbances 
ensue immediately — for example, when prussic acid is ingested. 

The onset may be slow and progressive or abrupt and sudden, and 
is followed by a stationary period, which is generally of quite short 
duration. As an example we may mention alcoholic intoxication. 
Drunkenness appears some time after the ingestion of the alcoholic 
beverage, and its disappearance is rapid and complete. Such is not 
always the case, however. The absorption of a great amount of alco- 



EVOLUTION OF DISEASES 391 

hoi may be followed by visceral lesions which are of subsequent and 
independent development. If the liver is affected, an acute steatosis 
may be observed, which rapidly causes death, accompanied by mani- 
festations of grave icterus. 

Similar remarks are applicable to phosphorus or cantharides 
poisoning. In both of these instances hepatic or renal lesions occur 
and continue to develop long after all the toxic substance has been 
eliminated. 

At other times symptoms persist because the poison has facilitated 
the development of an infection. In mercurial poisoning, a stomatitis 
or an enteritis, the work of the microbes of the mouth or the intestine, 
may produce gangrenous and ulcerous lesions in the mucous mem- 
branes altered by the mercury. In a similar manner the development 
of broncho-pneumonia consecutive to carbonic-oxide intoxication must 
be attributed to the intervention of microbes. 

Thus in all acute poisonings we must take into account both the 
primary and, as a rule, transitory effects produced by the poison, and 
their more or less deferred consequences, which are due either to vis- 
ceral lesions resulting from the poisoning or to secondary infection. 

Chronic intoxications are far more common and interesting. For 
years individuals absorb considerable quantities of poison without the 
least apparent derangement. During this long latent period the mor- 
bid phenomena develop insidiously; visceral lesions are produced, and 
then symptoms appear, either slowly, progressively, or even with an 
astonishingly abrupt intensity. 

The progressive development of morbid events is easily explained 
by the development and continuous aggravation of the lesions. The 
sudden and often unexpected appearance of the disturbances is refer- 
able to one of the following causes : sudden augmentation of the daily 
dose of the toxine, suppression of the toxine, or intervention- of a 
new mechanical, physical, chemical, or animate pathogenic agent. 

The influence of an increase of the habitual dose is easily under- 
stood. A man who is in the habit of drinking to excess will have an 
attack of intoxication or delirium as a result of indulgence greater 
than usual. A fresco painter who tolerates his saturnism will have an 
attack of lead colic after breathing more of the poison than usual — for 
example, after having scraped a wall painted with white lead. 

At first sight it is still surprising to observe disturbances follow 
the suppression of the daily toxine. The fact is that the poison has 
become necessary to the regular performance of functions and has 
been made, as it were, a constituent part of the cellular protoplasm. 
In other words, it is an indispensable excitant, and if it is lacking dis- 
orders become manifest, which disappear as soon as it is again admin- 
26 



392 INTRODUCTION TO THE STUDY OF MEDICINE 

istered. Such is the case with the alcoholic and the morphine eater, 
who are often seized with disquieting symptoms when they are forced 
to abandon their pernicious habit. As soon, however, as they take a 
dose of their usual poison, all the disturbances vanish. An idea of the 
results of a total suppression may be obtained by a consideration of 
the daily life of an alcoholic. On awakening in the morning, his ideas 
are not quite clear, and his hands are agitated with a continuous trem- 
bling. As soon as he takes a drink, however, the symptoms disappear, 
intelligence again becomes quite bright and the trembling ceases. 

The poison has therefore become indispensable to the regular 
activity of the organs. 

The visceral lesions produced in the course of intoxications, like 
those developing in the course of infections, often remain latent for 
a very considerable period. They may give rise to disturbances on the 
occasion of some intercurrent cause which breaks the unstable state 
of equilibrium of the organism. 

For instance, an alcoholic individual, who seems to be in good 
health, surfers from a traumatism, a sunstroke, or an infectious dis- 
ease, when he is at once seized with delirium tremens. The sudden 
intervention of a new cause provokes the appearance of symptoms. 
The same is true of an individual affected with plumbism. Lead colic 
is an acute episode in the course of a chronic intoxication; it occurs, 
as a rule, as the result of some occasional cause, particularly of an 
excess in drinking. 

The development of visceral lesions is generally caused by intoxi- 
cations and infections. These lesions, as we have repeatedly stated, 
develop independently, deriving no particular character from the cause 
or causes from which they originate. 

The symptoms and evolution of a nephritis, a cirrhosis, or a cardi- 
opathy do not differ according to the agent which has occasioned them ; 
on the contrary, everything depends upon the nature and extent of 
the lesions. 

It is readily understood that a profound but localized alteration is 
far better borne than a superficial but diffused one. Likewise, symp- 
toms are less marked when the interstitial tissue is affected than when 
the glandular cells are attacked. It is true that the organs comprise 
a much greater number of cells than is necessary for the continuation 
of life. From 40 to 50 per cent of the glandular tissues may be sup- 
pressed with impunity; one third of the liver may be removed, one 
kidney extirpated, or one lung excised, without any great disturbance. 
With certain glands, even very important ones like the pancreas, a very 
small part suffices for the regular performance of their functions. 

These remarks perfectly explain the frequency of latent affections. 



EVOLUTION OF DISEASES 393 

A visceral lesion may run its course silently for months or years 
without expressing itself by any symptom. The organic lesion will be 
discovered perchance. On auscultating the heart the physician may 
find an aortic insufficiency until then unsuspected, or, on examining 
the urine, he finds sugar or albumen, while no disorder whatever made 
him suspect the existence of diabetes or nephritis. 

Notwithstanding the absence of disorders, these lesions constitute 
a permanent danger, for sudden or unexpected death is often the con- 
sequence of such latent conditions. 

In certain cases symptoms appear progressively or abruptly, being 
excited by some intercurrent and often very slight cause. The organ- 
ism is in such a state of unstable equilibrium, however, that disturb- 
ances may appear on the slightest occasion. Thus, a hepatic cirrhosis 
may remain absolutely latent; then, in consequence of a cold, ascites 
rapidly develops, and from that moment all the manifestations of the 
affection are displayed. 

The symptoms produced in the course of a permanent affection are 
often transitory; they cease and subsequently reappear, although the 
lesion persists. We are thus led to say a few words in reference to 
intermittence in diseases. 

Without again referring at length to infections, we shall first recall 
the example of malaria. The paroxysms occur periodically, leaving the 
condition of health intact in the intervals. It is admitted in this in- 
stance that intermittence is explained by the life cycle of the parasite. 
However, in visceral suppurations the fever may also assume the same 
character. While the cause acts continuously, the organism acts only 
in an intermittent manner. The same fact is observed (and its inter- 
pretation then seems much easier) when there is excitation of a mu- 
cous membrane. Thus, in spasmodic laryngitis or croup, the glottic 
obstacle, though permanent, gives rise only to attacks of suffocation of 
a paroxysmal character. Although the lesion remains the same, and 
does not vary from one moment to another, it excites spasms only at 
intervals. Then, after an effort, perhaps as the result of exhaustion, 
the affection resumes a milder course. It may be remarked that physi- 
ology has prepared us to accept these results. For the production of 
a phenomenon, a series or a summation of excitations is often required ; 
reciprocally, the excitation persisting, the effect may cease. An ener- 
getic current applied to the pneumogastric nerve arrests the heart, 
but only for a moment, since, despite the persistence of the stimulant, 
the beating recommences. 

Similar phenomena are observed under a great number of cir- 
cumstances. Even traumatic lesions are not exceptions. The pain 
felt in old cicatrices on seasonal or barometric variations pre- 



394 INTRODUCTION TO THE STUDY OF MEDICINE 

sents a periodicity which is explained by the influence of cosmic 
variations. 

The mechanism of periodicity in chronic affections is a subject of 
special interest. This mechanism may easily be explained by one of 
the following two processes, as the case may be: At times there is a 
slow accumulation of toxic substances and the paroxysm breaks out 
when the toxines become too abundant; at other times there is a cir- 
culatory hindrance, and nutrition, although sufficient in the state of 
rest, is unable to supply the needs of the organ during the period of 
activity. 

In the former case, the paroxysm may be looked upon as a sort of 
discharge calculated to neutralize, eliminate, or modify the toxic sub- 
stances. There is a growing tendency to attribute to auto-intoxication 
an important role in the genesis of paroxysmal manifestations oc- 
curring in the course of a neurosis. The fit of epilepsy has been ex- 
plained in this manner. Whatever may be the value of this hypothesis, 
it is undoubtedly true that the patient feels better after a crisis: he 
finds himself relieved by a sort of salutary discharge. The same remark 
may also be applied to the intermittent manifestations which occur 
in the course of diatheses. An asthmatic and particularly a gouty 
paroxysm are prepared by modifications of nutrition, which is subse- 
quently improved in a notable degree. The subject experiences a feel- 
ing of well-being. Then, little by little, the disturbances slowly and 
insidiously return, until they end in a new attack. 

The second mechanism above referred to is much better known. 
It is best exemplified by arteriosclerosis. In this affection, the arteries 
having lost their elasticity, circulation is unsatisfactory: as long as 
the organs are at rest, reparation is sufficient ; as soon, however, as they 
become active, disorders become apparent. In this manner a syndrome 
is produced which can be studied in animals as well as in man — i. e., 
intermittent claudication (limping). Whenever the subject walks for 
some time the insufficiency of arterial circulation hinders the activity 
of the muscles and gives rise to limping. 

What is easily observed in the limbs is equally produced in the vis- 
cera. According to the felicitous expression of Grasset, an intermit- 
tent claudication of the organs exists. Visceral disturbances become 
manifest as soon as a more active circulation becomes necessary. A 
good many causes may therefore give rise to this phenomenon. As 
a clear illustration, we may take sclerosis of the coronary arteries. 
Although the circulation has become very defective, no disturbance is 
produced; then, all of a sudden, a paroxysm of angina pectoris occurs 
which seems to appear spontaneously and without any apparent cause. 
In reality, it is due to some gastrointestinal, pulmonary, cardiac, or 



EVOLUTION OF DISEASES 395 

nervous disorder. A too hearty meal, difficult digestion, exposure 
to wind, overexertion, a strong moral impression have demanded of 
the heart an increase in work. This organ, which accommodated itself 
to the ischaemia produced by the sclerosis of the coronaries as long as 
its activity was moderate, no longer receives a sufficient amount of 
blood under the new conditions. Therefore the first manifestation 
of a chronic, slow, and progressive process appears abruptly. At the 
end of a few minutes the symptoms subside, and the individual resumes 
the appearance of good health until the moment when a new attack 
occurs. In proportion as the attacks are repeated, however, the mi- 
nutest causes suffice to provoke their return. A time arrives when 
the attacks seem to be produced spontaneously ; the occasional cause is 
too slight to be recognised. 

The same thing may be repeated with regard to many other mani- 
festations. The attacks of asystole, despite the persistence of the 
lesion, are also intermittent; they appear on the occasion of some in- 
termittent cause, which will become slighter in proportion as the 
accidents are aggravated, and, in the end, will pass unnoticed; the 
paroxysm will possess the appearances of spontaneity. 

The same remarks are applicable to other organs and to various 
apparatus — lung, liver, kidney, and the nervous system. 

Latent Diseases. — If the accessory cause which explains the de- 
velopment of periodical accidents is lacking, the disease may remain 
latent. 

Diseases, even those that are acute, are sometimes unexpressed by 
any disturbance. Among the infectious diseases, we shall only men- 
tion typhoid fever and pneumonia. There are cases of typhoid fever 
in which the symptoms are so feebly marked that the subject continues 
to attend to his business. This is the form which has been well studied 
under the name walking typhoid fever. While generally innocent, this 
form does, however, occasionally expose the subject to terrible com- 
plications, and may end in rapid death by perforation of the diseased 
intestine. 

Pneumonia is quite frequently latent in the aged. No reaction is 
produced; the individual gets up, leads the same existence as on the 
preceding days; then he suddenly becomes ill and succumbs in a few 
minutes. The autopsy shows gray hepatization of one of the lungs, 
and the observer is astonished that lesions so strongly marked should 
have developed without giving rise to the slightest symptom. 

Among latent affections we may cite a goodly number of cases of 
pericarditis, pleurisy, and even acute meningitis. Consecutively to an 
otitis or a sinusitis, diffuse suppurations may invade the meninges 
without any reaction being produced, not even slight headache. 



396 INTRODUCTION TO THE STUDY OF MEDICINE 

Lastly, it must also be remembered that chronic affections of the 
organs, such as cirrhoses of the liver, nephrites, valvular lesions, and 
particularly aortic insufficiency, spinal and cerebral affections, gastric 
ulcer, and sometimes cancer, may remain latent for a great length 
of time, and they may subsequently produce rapid disturbances or 
even cause sudden death. They may finally give rise to no manifes- 
tation at all. They are revelations of the autopsy. 

The evolution of a disease may be modified by various superadded 
phenomena and by intercurrent complications. In certain instances 
the occurrence of a complication causes the primary phenomena to 
disappear. Nervous affections and parasitic diseases of the skin have 
been seen to stop for a time on the appearance of some acute infec- 
tion. Lastly, in certain instances, an existing manifestation sud- 
denly vanishes when a similar phenomenon develops at another point. 
This is known as metastasis. 

Metastasis. — Metastasis is the transportation of a morbid process 
from one point of the organism to another. In order for metastasis to 
exist, the transportation must be complete — viz., the primary lesion 
must disappear. 

According to this definition, the so-called metastatic abscesses are 
very improperly so named. In this case there is not a disappearance 
of the initial process, but a generalization of an infection. Nor are 
the cancer metastases to be admitted. When an epithelioma of the 
intestine is followed by the development of a similar neoplasm in the 
liver, it is a case of extension through embolism. 

Thus defined, metastases are quite rare. A few examples have 
been observed in infections — e. g., the urethral discharge often dis- 
appears when a gonorrhceal orchitis supervenes. A better example is 
furnished by the history of rheumatism: when cerebral manifesta- 
tions appear, the swelling of the articulations diminishes and the 
pains often disappear with astonishing rapidity; there is a transpor- 
tation of the fluxion which leaves the articulations to invade the nerv- 
ous centres. In fact, the congestive and fluxionary phenomena are 
the most easily displaced. The knowledge of these facts has led to 
an important therapeutic method — i. e., revulsion. When cupping is 
practised upon the thorax, pulmonary congestion diminishes; when 
an irritation is provoked in the intestine, the encephalonic or me- 
ningeal congestion is diverted. From this point of view calomel 
gives excellent results. By creating a new congestive process, it 
is possible to cause the older one to disappear — i. e., to provoke a 
metastasis. 

If we consider the diathetic affections, or, to speak more exactly, 
if we consider arthritism, we find well-known facts entering into this 



EVOLUTION OF DISEASES 397 

group. Between certain morbid manifestations a perfect balance 
exists, and the ancient physicians have laid much stress npon the 
diseases which it is frequently dangerous to cure. Facts of this kind 
are to-day regarded as doubtful, perhaps on account of their being 
difficult of interpretation. It seems certain, however, that the disap- 
pearance of an eczema may be followed by an attack of asthma, and 
a very curious balance exists between certain skin diseases and various 
internal manifestations — e. g., hemicrania, enteritis, etc. 

Gout may also alternate with various diathetic disorders. Its 
study also furnishes an excellent illustration of metastasis. An indi- 
vidual is seized with a very painful paroxysm; the big toe, much 
swollen and red, causes intense suffering. In order to mitigate the 
pain, he plunges his foot in cold water; relief is at first produced, but 
soon visceral symptoms appear, involving the heart, the brain, or the 
stomach — symptoms which are often very grave and sometimes fatal. 
It is then said that gout has retroceded or ascended. The idea of this 
misplacement may appear odd; but it must be recognised that to-day, 
just as in the past, no satisfactory explanation can be given. Several 
observations recorded as examples of retroceded gout are undoubtedly 
referable to gastritis or to degeneration of the myocardium, and espe- 
cially to uraemia. Nevertheless a few facts remain that can not be 
thus explained. For want of a better explanation, we shall consider 
them as belonging to the group of metastases. 

Recovery. — Whatever may be the disease under consideration, re- 
covery may take place gradually or abruptly. In the latter case a true 
crisis is produced; the symptoms yield at once; the previously dis- 
turbed organic functions are re-established, or they may even be aug- 
mented and exceed physiological limits. Thus in a great number of 
diseases the urinary secretion diminishes. At the moment of recov- 
ery there occurs a urinary discharge similar to that which we have 
noted in infections : a transitory polyuria appears during one or sev- 
eral days. This urinary crisis is of very common occurrence after 
intoxications, painful affections, and in the course of affections of the 
organs — e. g., liver, kidney, and heart. 

The same variations may be produced in the temperature. If 
hyperpyrexia has existed during the disease there will be hypothermia 
at the time of recovery, and vice versa. In a great number of intoxi- 
cations, as in certain infections, such as cholera, for example, the 
grave events are accompanied by a rectal temperature as low as 35.5° 
or 36° C. Subsequently, at the time of recovery, a reaction is pro- 
duced and the thermometer reaches 39° or 40° C. 

In the case of a transitory disease or affection, recovery of health 
may seem complete and the cure perfect. 



398 INTRODUCTION TO THE STUDY OF MEDICINE 

As regards chronic affections, the morbid symptoms may also 
decline, and, on a superficial examination, recovery may seem to be 
established and all the lesions repaired. In reality such is not the 
case. 

Every morbid manifestation lasting for some little time brings in 
its train irreparable lesions. The disorders cease because a series of 
modifications which assure compensation have been produced. There 
first occurs disappearance of altered elements, which are replaced by 
connective tissue — the cicatricial tissue which always comes to fill the 
vacant space created by the destruction of differentiated elements. 
The organism possesses such an overabundance of cells in its glands 
as well as in its most highly organized parts, such as the nervous cen- 
tres, that it does not feel the loss of a few of them. On the other 
hand, the healthy supplement the diseased parts, and compensating 
hypertrophies and hyperplasias are thus produced. This is a mechan- 
ism which we have studied at length in connection with morbid sym- 
pathies (page 328). The cardiac hypertrophy that assures the com- 
pensation of a valvular lesion or contributes to the re-establishment 
of the activity of a diseased organ, such as the kidney or lung; the 
hypertrophy of the bladder, which overcomes the difficulty of micturi- 
tion in cases of urethral stricture; the hyperplasia of the liver or 
kidney, which furnishes new elements to replace those which have 
been destroyed, for some time maintain an almost normal state of 
health. This re-establishment, however, is but apparent. Sooner or 
later a functional insufficiency appears, which brings fresh disorders 
in its train. 

Absolute cure is not possible save in traumatism. In nontrau- 
matic cases the functional disturbances may recede and disappear; 
the organism then seems to return to a state of health as perfect as 
before the disease. In reality, however, the pathogenic cause, whether 
toxic or infectious, has imposed a lasting modification upon the nutri- 
tion of the subject. This modification, which, as we have repeatedly 
stated, explains recovery, will carry the economy out of the physio- 
logical channel. So that after each morbid effect there still persist 
some changes which are often too small to be noticed, but which, if 
the pathogenic causes be repeated, may, by summation, result in more 
or less marked lesions, new disturbances, organic affections, or finally 
in death. 

Death. — Death may occur in two different ways : progressively, as 
is most frequently the case, or suddenly. Two varieties of sudden 
death are to be distinguished. At times the termination is foreseen. 
The physician can diagnosticate a disease or a lesion recognised to 
be capable of killing suddenly. For example, a person known to have 



EVOLUTION OF DISEASES 399 

aortic insufficiency may live for ten, twenty, or thirty years without 
suffering at all from his lesion; but he is liable to succumb at any 
moment. 

Facts of this kind are not legally considered as cases of sudden 
death. In legal medicine this distinction is reserved for unforeseen 
death, attacking individuals in apparently good health ; for it is dem- 
onstrated that a really healthy individual is not exposed to sudden 
death. Traumatism excepted, it may be affirmed that every individual 
succumbing suddenly was affected with a lesion which was until that 
moment latent. 

It is said, and constantly repeated, that sudden death is generally 
due to rupture of an aneurism, or to cerebral congestion. This is an 
error. According to the statistics of the Paris morgue, rupture of 
an aneurism is not encountered even in the proportion of 4 per 1,000. 
As regards cerebral congestion, Professor Brouardel declares he has 
never seen it in cases of sudden death. 

What is most frequently found is degeneration of the myocardium, 
aortic insufficiency, interstitial nephritis, gastric ulcer, and sometimes 
pleurisy or embolism. Finally, in some cases tuberculous meningitis, 
and especially suppurating meningitis induced by a purulent coryza 
or otitis, are observed. 

Since the time of Bichat, classical works repeat that death is 
effected through the lungs, heart, or brain. It is quite evident that 
death through the brain can no longer be admitted to-day; it should 
be said that death occurs rather through the medulla. Thus modified, 
the conception is still inexact. In fact, we must rise to a higher idea 
and look for the mechanism of death, not in an apparatus, but in a 
general disturbance, in some modification affecting the function of 
the cells. We are thus brought to consider death as connected with an 
arrest of cellular nutrition. 

In certain instances this arrest of nutrition may occur under the 
influence of violent excitation, as is the case in nervous shock. The 
exchanges between the morphological elements and the surrounding 
medium are suppressed; there is a retention of noxious products in 
the cells and lack of renovation of the humoral medium. 

In most cases death occurs because waste substances accumulate 
in the humours and arrest the nutritive exchanges. This is what nota- 
bly occurs when lesions exist in the liver and the kidneys. Hence, 
when death is spoken of as occurring through these organs, it is 
meant that there has been an auto-intoxication of the organism as the 
result of their disorders. Similarly, when there is an arrest of the 
heart — namely, syncope — or suppression of the pulmonary emunctory 
— namely, asphyxia — death results from a lack of organic depuration. 



400 INTRODUCTION TO THE STUDY OF MEDICINE 

The blood during cardiac arrest no longer carries to the various cells 
the substances necessary for their nourishment, and is therefore 
unable to rid them of useless materials. In asphyxia the absorption 
of oxygen and the rejection of carbonic acid do not take place, and 
this also results in intoxication. 

Therefore, in thus attempting to penetrate the mechanism of death, 
we reach the conclusion that the fatal termination can not be ex- 
plained by the lesion or the suppression of an organ. Those who have 
upheld this hypothesis have considered the apparent phenomenon; 
they have given a formula applicable only to higher individuals ; they 
have proposed a restricted definition for a general manifestation. 
The suppression of a function can not characterize a process which is 
observed when that function no longer exists. 

Death, like life, can not be understood except when all series of 
beings are taken into consideration. Its definition is therefore to be 
looked for in the disturbances, not of an apparatus, but of all the cells. 
In other words, in the higher forms of life we must consider two orders 
of phenomena: (1) a suppression of functions which does not consti- 
tute death, but leads to it if the disturbance persists; and (2) an 
arrest of nutrition which indicates the true cessation of life. The 
suppression of cardiac pulsations, for instance, is not synonymous 
with death, for if they recommence, the individual revives. The same 
is true as regards suppression of the pulmonary function. Puncture 
of the medulla itself is not necessarily fatal, since artificial respira- 
tion may maintain life. All these lesions and disturbances only pre- 
pare the fatal termination. 

Now, with reference to nutrition, we have shown that cellular 
nutrition and the organs concerned therein should be considered sepa- 
rately. Cellular nutrition is the general phenomenon essentially char- 
acterizing life; its suppression characterizes death. If we consider 
the unicellular beings, we readily understand that nutrition will stop 
under two quite different conditions. Sometimes the cell will lose 
its aptitude to derive from the liquid medium wherein it lives the 
materials necessary for its incessant renovation, and to throw out 
those that have become useless or harmful. These conditions are 
realized under the influence of certain too violent excitations' or of 
certain lesions produced by mechanical, physical, or chemical agents. 
At other times the medium itself becomes unfit for maintaining life, 
on account of the nutritive elements having been exhausted or the 
cellular wastes having accumulated. 

These extremely simple facts will permit us to explain the mechan- 
ism of death in higher beings. In fact, we find the same two con- 
ditions. 



EVOLUTION OF DISEASES 401 

A shock or violent excitation may cause arrest of nutrition; but 
it is readily understood that the pathogenic cause can hardly act at 
once upon all the cells of the economy. This hypothesis, which might 
be maintained with regard to some poisons, is hardly probable. In 
most cases the arrest of general nutrition is produced through the 
nervous system. Let us take, for example, a violent traumatism. In 
the case of a unicellular being it inhibits directly the nutritive activ- 
ity of its protoplasm ; in the case of a higher organism it produces an 
excitation of the nervous terminations which gives rise by reflex action 
to the morbid state already studied at length under the name of nerv- 
ous shock. The mechanism is more complex in the latter case, but 
it is essentially the same. It also intervenes in internal traumatisms 
— for example, when a pulmonary embolism, a cerebral embolism, or 
hemorrhage cause sudden or speedy death. 

Toxic substances also kill by arresting cellular nutrition. Some- 
times they form stable combinations with the protoplasm; sometimes 
they seem to act by transmitting to it a sort of molecular vibration. 
In considering a unicellular being, it is easy to conceive the mechan- 
ism of death in both cases. In individuals of a higher rank, however, 
it would be necessary to admit that all the cells are simultaneously 
killed by the poison — a thing that can never be realized. Certain 
highly organized cells, notably the nerve cells, are the first to die. If 
the being succumbs, it is because disorders have been secondarily pro- 
duced in the humoral medium — i. e., in the plasma in which the cells 
are immersed. The phenomena thus become more complex, a fact 
that is due to the greater complexity of the organism. 

In order to understand the mechanism of death we must recall 
what has been stated in connection with nutrition. 

The higher beings are provided with an internal medium whose 
constitution must remain fixed and invariable. Numerous organs 
work to this end. If one of them should stop working, if others 
should be unable to take its place, death will be the consequence. 

Let us see the principal cases which may be encountered. 

1. The materials of renovation are no longer furnished to the 
blood, because the subject is submitted to inanition, or because the 
digestive canal has become incapable of transforming or absorbing 
food; death ensues because the first act of nutrition — assimilation — 
no longer takes place. 

2. The result is similar when the requisite amount of oxygen is 
not furnished to the cells, either because the red blood corpuscles are 
not sufficiently numerous, or else they are no longer able to fix this 
gas, as occurs in carbonic-oxide poisoning. 

3. In case of arrest of the circulation, the suppression of cardiac 



402 INTRODUCTION TO THE STUDY OF MEDICINE 

activity causes death because cellular renovation is no longer effected, 
and the blood, which serves at the same time as a way of excretion, 
ceases to throw out the useless substances. 

4. The situation is quite similar when respiration is arrested: the 
cells succumb because the gaseous exchanges are suppressed; oxygen 
no longer arrives and carbonic acid is no longer exhaled. 

5. Lastly, the arrest of nutrition may result from lack of depura- 
tion consecutive to alterations of the emunctories. The products 
of disassimilation are no longer rejected; they saturate the medium 
and prevent diffusion of harmful substances out of the cell. The 
lesions of the liver, kidney, and highly vascular glands kill by this 
mechanism; they arrest nutrition by virtue of the auto-intoxication 
which they produce. 

In brief, if the proceedings called into play are multiple, the final 
result is always the same. In vegetables as well as in animals, in uni- 
cellular beings as well as in those placed at the top of the scale, death 
is always produced through the same mechanism. 

Therefore, modifying the usual formula, we shall say: Death is 
the result of an arrest of cellular nutrition, either because the proto- 
plasm becomes incapable of carrying out the double movement of 
assimilation and disassimilation, or because the medium in which the 
cells are immersed or in contact undergoes modifications rendering 
exchanges impossible. 

The arrest of nutrition is a general phenomenon applicable to all 
beings. In all it is due to either of the two mechanisms above indi- 
cated. In the higher organisms, however, it occurs under conditions 
more and more complex in proportion to the growing complexity of 
the apparatus concerned in assuring the activity of the protoplasm 
and the renovation of the organic medium. 



CHAPTER XXI 
EXAMINATION OF THE SICK 

General appearance of the patient— Posture— Facies— Corporeal deformities— Ex- 
amination of the integuments— Systematic examination of the various appa- 
ratus—General rules for the examination of the circulatory and respiratory 
organs, the digestive canal, liver, spleen, pancreas, peritoneum, urinary and 
genital organs, and the nervous system. 

The examination of patients may be made in several ways. It is 
customary, however, to follow an almost identical course in all cases. 
The external appearance, the facies, and posture of the patient are 
first noted; at the same time some questions are asked him as to 
pain and other disturbances from which he may be suffering. The 
first impressions thus obtained give an idea of the nature of the dis- 
ease and serve as a guide to exploration. The hereditary and per- 
sonal antecedents and present symptoms of the patient must then 
successively be considered. 

As already stated, the first question asked of the patient is in- 
tended to locate the seat of his pain. In most instances the phenom- 
ena of pain lead us to an immediate recognition of the parts affected. 
Spontaneous pain and that which is excited by touch or movement, 
and which may therefore be located with greater precision, are of 
unquestionable semeiological value. It is well to remember, however, 
that the investigation of the phenomena of pain may also lead to 
error. For instance, an individual complains of pain in the stomach 
and frequent vomiting. Gastralgia is at once thought of, and the 
stomach is treated with negative result. Here failure to relieve the 
patient is due to the fact that the gastric symptoms were those of 
ataxia. At other times patients with some spinal disease complain 
merely of pains irradiating in the limbs or located in one or several of 
the joints; these pains are too hastily referred to rheumatism, and 
sodium salicylate or antipyrine are prescribed without effect. 

In this connection the morbid sympathies which unite the heart 
and the lungs are pre-eminently instructive. Physicians are often 

403 



404 INTRODUCTION TO THE STUDY OF MEDICINE 

consulted by patients complaining of palpitation of the heart. In 
fact, the pulse is found to be quick, beating from 100 to 120 per min- 
ute. Bromide is prescribed with no benefit, and digitalis causes aggra- 
vation of the symptoms. Here nonsuccess is due to the fact that 
these so-called cardiac patients are in reality pulmonary consump- 
tives; they are subjects of lung lesions which are unattended by any 
lung symptoms, but which could readily be discovered by means of 
auscultation. On the other hand, many young women complaining 
of slight but persistent cough, complicated at times by hemoptysis, are 
treated as consumptives, dosed with cod-liver oil and creosote, and re- 
peatedly cauterized at the apex of their thoraxes, and yet the respira- 
tory apparatus is intact or but secondarily disturbed. The initial 
lesion is seated in the heart : it is simply a case of mitral stenosis. 

These few examples sufficiently prove the necessity of always exam- 
ining all the organs in a systematic manner. This is the only means 
of avoiding such gross errors as have just been referred to. 

General Appearance of Patients 

Before entering upon a methodical examination of the organs, 
however, it is necessary to exactly observe the patient's attitude, facies, 
and general appearance. While ancient physicians knew nothing of 
percussion, auscultation, or bacteriology, and the methods of explora- 
tion employed by them were rudimentary, they have nevertheless left 
us certain precepts which it would be an error to ignore. At the 
present day too much is made of scientific procedures. 

Attitude, Decubitus. — In case an individual is so seriously affected 
as to be compelled to lie in bed, his posture must first be noted. 

In the first place, there is the horizontal posture upon the back. 
As a rule, this is the position assumed by individuals in suffering, 
and by those who are exhausted or have lost consciousness. The same 
position is taken by those attacked with hemiplegia, although some- 
what modified by the fact that the paralyzed side, being less strong 
than the other, shrinks, as it were, and the healthy side appears to be 
prominent. In a case of cerebral anaemia the head is low; in that of 
congestion the head is raised high and supported by pillows; the 
relief produced by this position is so considerable that even patients 
in a semicomatose state constantly ask to have their heads elevated. 

Another variety of horizontal decubitus is the lateral, which is fre- 
quently observed in cases of thoracic affections. 

When an individual has pain in the side not connected with any 
alteration of subjacent organs — in other words, when he suffers, for 
instance, from neuralgia, pleurodynia, or muscular rupture — he lies 
upon the affected side. The compression thus produced diminishes 



EXAMINATION OF THE SICK 405 

the pain ; a feeling of relief is experienced by pressing the hand upon 
the affected part or by compressing it against the bed. 

The phenomena are more complex in cases of acute affections of 
the respiratory passages. At the outset the patient lies mostly upon 
the healthy side; later on he lies upon the diseased side, in order 
to breathe more freely with the intact half of the chest. In case of 
pleurisy it is altogether impossible for the patient to lie upon the 
healthy side, for the effusion, obeying the laws of gravity, compresses 
the mediastinum and presses against the intact side, thus preventing 
respiratory movements. 

In cardiac diseases the victims lie upon the right side. This is an 
exaggeration, as it were, of a normal phenomenon; even in good 
health it is more or less uncomfortable to lie upon the left side. 
At a more advanced stage the sufferer assumes an altogether peculiar 
position: he sits with his head and shoulders supported by pillows; 
the legs are dependent, while his arms are kept in a motionless posi- 
tion with a view to furnish a point of support to the auxiliary muscles 
of respiration. 

In case of abdominal superficial pain, the sufferer will likewise 
try to exert pressure upon the abdomen : sometimes he will lie ex- 
tended upon his back with the thighs and legs bent, the hands widely 
opened and pressing upon the abdomen ; at other times he will simply 
lie upon his abdomen. If the pain is very intense there will be agi- 
tation and frequent change of position. In some instances the de- 
cubitus is quite peculiar and might be called semilunar incurvation. 
The patient is rolled upon himself; the vertebral column describes a 
half circle, and the thighs are flexed upon the pelvis. This position is 
observed in cases of peritonitis, and in hepatic or renal colic. It is 
also well to be acquainted with the odd positions assumed by those 
suffering from gastric ulcers. At the time of a paroxysm the patient 
instinctively assumes a posture calculated to avoid contact of the 
food with the diseased walls. If the anterior surface is diseased, he 
lies upon his back ; if the posterior surface is the site of ulceration, he 
lies upon his abdomen ; he lies upon his right or left side according as 
the ulcer is situated upon the left or right side. The importance of 
these various attitudes is readily understood with reference to the 
diagnosis of the site occupied by the gastric lesion. 

Finally, there is another posture which is frequently observed in 
tubercular meningitis: the child lies upon one side, with the legs 
strongly flexed upon the thighs. 

The Facies of Patients. — Next to the posture, the facies of the 
patient must be noted. A great number of nervous or mental de- 
rangements impart to the face an altogether peculiar expression. In 



406 INTRODUCTION TO THE STUDY OF MEDICINE 

some instances the peculiar appearance results from paralysis of cer- 
tain muscles — e. g., the immobility of the eyes in external ophthal- 
moplegia, the crying countenance in labio-glosso-laryngeal paralysis.- 
In other cases the features remain motionless — e. g., in paralysis agi- 
tans; or the integument loses its property of contractility, as is ex- 
emplified by the marblelike countenance in sclerodermia and by the 
lunar facies of myxcedema subjects. In other instances parts become 
unduly developed, as occurs in acromegalia, or they become asym-. 
metrical. Paralyses of the seventh pair, whether central or periph- 
eral, associated with or without hemiplegia; paralyses of the motor 
oculi, conjugate deviation of the head and eyes, glosso-labial hemi- 
spasm of hysterical subjects, the facial trophoneurosis of Eomberg, 
all give rise to absolutely characteristic deformities. 

Likewise, in the course of various neuroses the facies offers some 
peculiar characters. The staring and ecstatic expression of hysterical 
patients, the stupefied aspect of an epileptic after an attack, the par- 
ticular countenance imparted by the exophthalmia of Graves's dis- 
ease, represent as many well-known examples. 

The expression of the physiognomy is of great importance in the 
diagnosis of cerebral diseases. According to the type of mental de- 
rangement, the countenance is calm or agitated, indifferent or pre- 
occupied, depressed or inspired. The contracted visage of the lype- 
maniac, the satisfied countenance of the general paralytic, and the 
wandering look and trembling lips of the alcoholic are also matters 
of common observation. 

We can not undertake to describe all the different appearances 
which may be observed in various diseases. We shall recall the ade- 
noidian facies, characterized by a stupid expression, transversely flat- 
tened nose, half-open mouth, and effaced naso-genian folds ; the facies 
of drinkers, characterized by a nose increased in size and covered with 
small veins; the mitral facies, with bluish lips, cyanosed cheeks, and 
puffed skin; the aortic facies, intensely pale; and the Brightic facies, 
swollen and whitish, etc. 

We must dwell somewhat longer upon the modifications, and par- 
ticularly the dyspnoea produced by thoracic diseases, and upon abdom- 
inal affections. 

Three types of dyspnoic facies have been distinguished. One is 
due to defective inspiration. For example, there may be in the larynx 
some trouble caused by a foreign body or a diphtheritic pseudo-mem- 
brane, in which case the patient remains sitting with the neck 
strained, eyes protruded, nostrils dilated, and the face very pale. In 
the young each inspiration produces a visible depression above the 
sternal notch and along the border of the false ribs : this is the 



EXAMINATION OF THE SICK 407 

suprasternal and infrasternal retraction caused by the action of atmos- 
pheric pressure. 

In case of expiratory disturbance the appearance is entirely differ- 
ent. The face is flushed, puffed, and bluish; the cervical veins are 
much distended; the eyes are motionless, half closed, and tears flow 
from the eyelids. This is the asphyxial facies. 

The third type occurs in consumptives. Its characteristics are, as 
every one knows, emaciated figure, protruding and red cheeks, fine 
nose with a jerking respiration, difficult speech, and often extinguished 
voice. 

Of the abdominal facies several varieties are admitted. 

In the first place there is the facies grippe, which is met with in 
grave lesions, in peritonitis, intestinal occlusion, and at times in 
hepatic and renal colic. The striking feature is the considerable 
diminution in the size of the features; the face appears to be 
shrunken and diminished; the nose is thin, elongated; the muscular 
fibres have retracted, and this renders the osseous prominences more 
appreciable. The skin is pale and often covered with cold sweat; the 
integument loses its tenderness and elasticity; hence, the folds made 
in it persist for quite some time. 

In children suffering from digestive disorders and marasmus the 
features are drawn, the furrows deepened, the neck hollow and ema- 
ciated. The facial expression recalls that of a little old man. 

A third type is represented by the cholera facies. The integument 
is violet, the nails dark, the lips blue, the eyes sunken in their orbits; 
the extremities, nose, and lips feel cold to the touch, and even the 
breath is cold. This special type, realized to its highest degree in 
cholera, is encountered in a great number of other diseased condi- 
tions accompanied by choleriform manifestations; it may almost be 
designated as the facies of agony. 

Three more particular facies may be admitted: the syncopal, the 
apoplectic, and the agonal facies. 

Syncope is characterized by an abrupt arrest of the heart; the 
individual becomes completely pale, respiration is suspended and the 
pulse imperceptible. In case of apoplexy the patient is motionless 
and lies upon the back; all the functions are in abeyance; breathing 
and circulation alone persist. Even these, however, are profoundly 
modified; the breathing especially is noisy and often stertorous. 
Finally, when agony arrives, as it does in most acute or chronic dis- 
eases, the cerebral functions are gradually suspended; respiration 
is painful and slow, the skin retracts, the nose is tapering, the eyes 
are dull, half closed, and glassy. Then breathing is gradually ar- 
rested ; after a few minutes of apncea it is resumed, but again stops ; 
27 



408 INTRODUCTION TO THE STUDY OF MEDICINE 

finally, a last inspiration takes place, and often the body is shaken by a 
slight spasm; the pupils suddenly dilate and the extremities are in 
complete relaxation. This is death. 

Corporeal Deformities. — In order to complete the study of the 
external habitus of the patient, corporeal deformities must be looked 
for, the existence of which is often of very great semeiological im- 
portance. 

The patient should be examined, when possible, both in the re- 
clining and upright position. The appearance of external forms may 
be noted in these two positions; moreover, it is well to instruct the 
patient to take a few steps, which may cause certain symptoms to 
become more manifest. 

Deformities may be general or partial. 

The general deformities are, as a rule, referable to alterations of 
the skeleton. Kickets and, less frequently, osteomalacia produce de- 
formities which may be very extensive. The appearance of a rachitic 
is a familiar one : the child's stature remains short, while the head 
is voluminous, with tardily closed fontanelles, the spine is incurved, 
the ribs are deviated so as to form two prominences, the pelvis is 
deformed, the limbs are curved, and the epiphyses too voluminous. 

Furthermore, it is well to know that even a partial lesion, provided 
it is profound, may cause secondary deformities modifying the entire 
architecture of the body. Such is the case with Pott's disease. 

Finally, general deformities may be produced by muscular atro- 
phies, provided the latter be extensive and involve most of the muscu- 
lar system. 

Partial deformities must be looked for successively in the head, 
trunk, abdomen, and limbs. In all regions deformities may depend 
upon some lesion of the skin or subcutaneous cellular tissue (derma- 
titis, cicatricial retractions, keloids, tumours, abscesses, oedema, etc.), 
or the vessels (aneurism, varices), or the muscles, skeleton, and, in the 
case of the head and trunk, of subjacent organs. In the head, deform- 
ities may affect the cranium ; they are referable to the epoch when the 
sutures, not having yet been effected, the lesions of the brain and me- 
ninges induce deformities of the skull, which moulds itself upon sub- 
jacent parts. It will suffice to mention hydrocephalus as an example. 

Of the main deformities affecting the face may be cited tropho- 
neurosis, the deviations due to paralyses or contractures of the mus- 
cles supplied by the seventh pair, fluxion and swelling of the parotids 
(parotiditis and mumps), and the protrusions caused by suppura- 
tion or tumours in more deeply seated parts, especially the sinuses 
of the face. 

Thoracic deformities, apart from those produced by rickets, are 



EXAMINATION OF THE SICK 409 

due to affections of the lungs, and, less frequently, of the heart. 
At times they are bilateral and symmetrical, as in the case of pul- 
monary emphysema ; at other times fhey are limited to one half of the 
chest, as occurs in pleurisy, pneumothorax, pleuro-pulmonary cancer, 
and tumours of the mediastinum. The diseased side is expanded and 
remains so even during expiration, which thus exaggerates the differ- 
ences. In case of chronic pleurisy, retraction of the organized exudate 
consecutively produces flattening of the affected side. 

There are also partial protrusions due to the presence of aneurism, 
abscess, or empyema bulging exteriorly under the form of a large 
tumour, which sometimes presents pulsations (pulsatile empyema). 

Alterations of the heart are less frequently productive of deform- 
ities. In case of considerable hypertrophy or pericarditis with profuse 
effusion prominence of the precordial region is observed. 

Likewise the deformities of the abdomen may be general or par- 
tial. The abdomen is distended and increased in size in case of 
ascites, tympanites, and acute or chronic peritonitis. In other in- 
stances a region presents an anomalous prominence — e. g., consider- 
able hypertrophies of the liver or spleen are expressed by a tumefac- 
tion of the hypochondrium, which is quite notable when the patient 
is standing. The lower abdominal organs very frequently give rise 
to deformities : a distended bladder, a uterus that is gravid or full of 
fibromata, and ovarian cysts are the most important causes. 

Examination of the external anatomy of the different members 
of the body, and particularly the extremities, should never be neg- 
lected. In fact, they may present numerous trophic disorders, many 
of which are of certain semeiological value. Some deformities are 
connected with nodular rheumatism, while others are due to chronic 
gout. There is a morbid state characterized by considerable hyper- 
trophy of the extremities — namely, acromegalia. Finally, there may 
be observed upon the third phalanges of the fingers the so-called 
nodes of Heberden; the so-called nodes of Bouchard upon the sec- 
ond phalanges, and connected with nutritional disturbances, partic- 
ularly with dilatation of the stomach ; the spatular fingers met with in 
children suffering from congenital cyanosis; the Hippocratic fingers, 
characteristic of tuberculosis; and the pneumic arthropathies of 
Marie, which occur when pulmonary respiration is greatly embar- 
rassed. 

The study of deformities of the hands will be completed by look- 
ing for a manifestation described by Landouzy under the name camp- 
todactylia. This state, which should not be confounded with retraction 
of the palmar aponeurosis, is observed in arthritics, and consists in the 
impossibility of fully extending the fingers, particularly the fifth. 



410 INTRODUCTION TO THE STUDY OF MEDICINE 

Examination of the Integuments 

A rapid examination of the skin should follow that of the general 
appearance of the patient. 

The colour may be modified over the entire body or the greater 
part of it, or only over a certain region. 

In some instances the skin is pale and discoloured. It presents a 
peculiar white, waxy hue in anaemia; the mucous membranes of the 
lips, gums, eyes, and genital organs are also pale. At certain points, 
especially at the lines of the face, a bluish hue is observed, which is 
particularly pronounced in anaemia of young women and is known as 
chlorosis. The appearance is so characteristic that the diagnosis is 
made at a glance. It is well to remember, however, that certain symp- 
tomatic anaemias may assume the mask of chlorosis in young women, 
as is observed, for example, in certain cases of tuberculosis or syphilis, 
in the course of gastrointestinal disturbances and especially in un- 
complicated mitral stenosis. 

Chronic intoxications by carbonic oxide, or lead, give rise to some- 
what particular anaemic conditions. The same is true of repeated 
hemorrhages and, above all, metrorrhagias. One of the most typical 
forms is the anaemia of cancer subjects ; their colour is of an absolutely 
characteristic straw-yellow hue. This appearance, taken in conjunc- 
tion with the emaciation, permits the observer to confidently diagnos- 
ticate the existence of cancer. Of the other affections producing pale- 
ness it will suffice to mention pernicious anaemia, leucaemia, amyloid 
degeneration, and Bright's disease. Acute articular rheumatism de- 
serves special mention because of the intense paleness and profuse 
odorant sweats characterizing it. 

Finally, paleness of the integument may result from vascular 
spasm; in this case, however, it is transitory. It occurs under the 
influence of emotion or of anger, during chills, and particularly in 
leipothymia and syncope. 

Congestion of the skin is of quite frequent occurrence, but, as a 
rule, it is local. In plethoric individuals the red colour is appreciable 
only on the face and at times in the hands. This condition is known 
as sanguineous temperament, which appears to be dependent upon a 
peculiar state of the circulation rather than upon a real augmenta- 
tion in the amount of blood. 

General or at least very extensive cutaneous congestions may occur 
in the course of a great variety of affections. Erythema is then said 
to exist. In its simplest expression erythema consists in redness which 
can be dispersed by pressure. In a great many instances, however, 
a further development of the phenomenon takes place: slight hemor- 



EXAMINATION OP THE SICK 411 

rhages or exudations are produced which may simply infiltrate the 
skin, as in urticaria, or raise the epidermis and thus give rise to bullae 
(erythema multiforme). 

The redness characterizing eruptive fevers — measles and scarlatina 
— as well as the rashes occurring as epiphenomenon in the course of 
most varied infections, particularly at the beginning of smallpox, are 
nothing more than erythemata. 

In order to avoid grave error in interpretation, it must be remem- 
bered that in certain individuals, especially in women of nervous tem- 
perament, vasomotor disturbances are easily produced. These are gen- 
erally limited to the face and chest, and become apparent when the 
physician begins the examination of the patient. They are called pudic 
erythemata. 

Localized redness, especially in the face, may be observed; such, 
for example, is the redness of the cheeks in pneumonia. 

Examination of the integument may also reveal various altera- 
tions, some of which are of importance from the standpoint of general 
pathology, while others, on the other hand, enter into the group of 
skin diseases. Thus we may find hemorrhages (purpura, ecchymoses), 
inflammations (erysipelas, eczema), vesicular lesions (herpes) or 
bullae (varicella, pemphigus), pustular inflammations (acne, ecthyma, 
variola), etc. We can not, of course, dwell upon all these lesions, 
which should always be carefully noted. 

Apart from the red colour dependent upon active congestion, there 
is also a blue colour referable to passive congestion. When the latter 
hue is general, it indicates profound asphyxia — i. e., a very great dis- 
turbance of hematosis. This condition occurs in cardiac or pulmonary 
insufficiency, and in grave adynamic states, such, for instance, as the 
algid stage of cholera. In all these cases cyanosis is especially marked 
in the extremities, hands and feet, the face, and particularly in the 
lips. It will suffice to remember the appearance of a patient suffer- 
ing from cardiac disease during the period of asystole. 

Cyanosis is local when it is due to compression of a large vessel; 
it may then serve to diagnosticate an intrathoracic tumour. 

The skin may likewise present anomalous colours resulting from 
the deposition of yellow or brown pigment. 

Every one is familiar with the yellow hue of icterus, which first 
becomes apparent in the conjunctiva, where it must always be looked 
for, since this localization serves as a point of differential diagnosis 
from the yellowish hue common to conditions of anaemia, saturnism, 
malaria, and cancer, which at times recall the colour of icterus. 

When there is a deposit of brown pigment, the examination of the 
mucous membranes is also of great importance. There exists a special 



412 INTRODUCTION TO THE STUDY OF MEDICINE 

affection connected with alterations of the suprarenal capsules and 
semilunar ganglia, designated as Addison's disease, and characterized 
by a brownish colour of the skin and by the presence of brown or slaty 
spots upon the mucous membrane of the mouth. This latter localiza- 
tion differentiates Addison's disease from other melanodermias, for 
example, from those observed in consumptives suffering from intes- 
tinal lesions, in individuals affected with malarial cachexia, in certain 
diabetics, etc. 

Examination of the integument must include a search for cicatrices. 
This exploration is sometimes of the first importance, since it may 
furnish a clew to antecedent pathological occurrences which are un- 
known to, forgotten, or denied by the patient himself. Of the cutane- 
ous cicatrices some are of traumatic origin and of little importance; 
others are referable to destructive affections of the skin or mucous 
membranes, such as acne, ecthyma, variola, tuberculosis, and, above 
all, syphilis. The syphilitic gummata are frequently seated upon the 
inner face of the tibia. These consist of round, sometimes confluent 
and polycyclical lesions; the central portion is colourless, white; the 
peripheral portion is formed by a brown circle. It is impossible to 
exaggerate the importance of this stigma which should lead to the 
institution of specific treatment, the only one capable of saving the 
patient. It is comprehensible that the smallest cicatrix presents a 
semeiological value of the highest importance in the case of an indi- 
vidual suffering from aphasia or apoplexy, or fallen into a state of 
helplessness. 

Other cicatrices also possessing a certain importance are repre- 
sented by vibices. The best known type is that observed in women who 
have been pregnant : the skin of the abdomen is covered with whitish 
stripes due to rupture of the elastic fibres. The same lesions occur 
whenever the skin is too much distended : they are found on the chest 
during and after a pleurisy; they are also observed in individuals who 
have rapidly grown; they are of frequent occurrence upon the outer 
side of the thighs in consequence of an attack of typhoid fever. 

After inspection of the skin palpation is practised, which furnishes 
information as to the elasticity, dryness, and temperature of the in- 
tegument. The skin loses its elasticity to such a degree in grave dis- 
eases, especially in affections of the alimentary canal, that it preserves 
for a moment the folds made on it. This phenomenon is very marked 
in enteritis of children, in intestinal occlusion, and in cholera. 

The skin is thickened and indurated in certain affections, such as 
ichthyosis, scleroderma, etc. It is dry in grave infections and in dia- 
betics; the return of moisture is a good sign, constituting one of the 
manifestations of defervescence. In other cases sweats are exagger- 






EXAMINATION OF THE SICK 413 

ated, either all over the skin or in certain portions thereof, and they 
may be of an anomalous character. Coloured, sanguinolent, clammy, 
and odorant sweats have been recorded. In acute articular rheu- 
matism the body especially is covered with profuse sweats having a 
strong, almost characteristic odour. The odour of cutaneous perspira- 
tion is modified in a great number of morbid states — e. g., in gastro- 
intestinal dyspepsia, in urinary affections, and in infectious diseases, 
such as typhoid and typhus fever, cholera, etc. 

Palpation likewise furnishes important information in regard to 
temperature. In some instances it reveals a thermal rise limited to a 
certain region, and thus leads to the discovery of some local inflam- 
mation; in other cases it indicates a general modification. Practice 
enables one to readily appreciate the variations of cutaneous heat. 
It should be well known, however, that palpation does not always 
furnish exact information as to the systemic temperature. There may 
exist dissociation — viz., the temperature of the skin may at times fall 
considerably, while central temperature is above the normal. Such, 
for instance, is the case in the first stage of intermittent fever. 

Examination of the skin must be completed by that of its adnexa — 
i. e., of the nails and hair. 

The nails often present trophic disturbances. In the course of 
the most varied diseases they become thin to such a degree that, after 
the termination, a more or less profound transverse furrow is observed. 
In other instances they become brittle, and are striated longitudinally. 
In chronic tuberculosis they thicken, assume the incurvation of a bird's 
beak over the digital pulp, and, conjointly with the transversal enlarge- 
ment of the last phalanges, they contribute to impart to the finger 
that peculiar appearance which is designated as Hippocratic finger. 

Analogous trophic disturbances are observed in the hair, which 
becomes dry, brittle, and easily falls out. Without speaking of affec- 
tions of the pilous system, we shall confine ourselves to a simple men- 
tion of the early baldness of arthritics, and the alopecia of syphilitics, 
which denudes the scalp in a diffused manner and not infrequently 
involves the eyebrows. 

Examination of the integument may often reveal alterations of 
the subcutaneous cellular tissue. (Edema, tumours, pseudo-lipomata, 
and tophi are recognised at a glance, and may guide the physician 
in his task of clinical analysis. The same is true of dilated veins, the 
presence of which indicates the development of a collateral circulation 
and leads to the discovery of deep-seated disorders. 

Examination of the Lymphatic Glands. — Either at the beginning of 
or during an examination the state of the lymphatic glands must be 
inquired into. In certain instances these glands are so greatly enlarged 



414 INTRODUCTION TO THE STUDY OF MEDICINE 

as to form tumours readily appreciable at first glance. Tubercular, 
cancerous, and suppurative glands acquire a considerable volume. In 
the majority of cases, however, they are to be sought for by means 
of palpation. Particularly the glands of the neck, groins, and axilla? 
must be explored, and less frequently the mastoid, the occipital, and 
the deep-seated glands, while those in the iliac fossa are readily dis- 
covered by palpation. The mesenteric, and especially the tracheo- 
bronchial ganglia, require a more delicate method of exploration, to 
which reference will be made in connection with examination of the 
abdomen and thorax. 

Ganglionic hypertrophy may be local or general. In the former 
case it involves a certain group of glands and indicates an inflamma- 
tory or other lesion of the corresponding organs. In the latter case, 
if the subjects are young children and the enlarged glands are numer- 
ous but not very voluminous, tuberculosis must be suspected: micro- 
polyadenitis is of great semeiological value. In adults, ganglionic 
hypertrophy is met with in a great number of acute or chronic infec- 
tions, notably in syphilis. Finally, more voluminous adenopathies may 
characterize a particular disease — viz., lymphadenitis. 

When an idea as to the state of the patient is formed by means of 
a rapid general examination, then all the organs and apparatus must 
be systematically passed in review. It makes no difference with what 
part of the body examination begins; the observer will generally be 
guided by the first information acquired. The disturbances first expe- 
rienced, the seat of pain, and the results of interrogation serve as 
guides. It is therefore well to begin with that apparatus which appears 
to be most affected. With a patient who complains of pain in the side, 
coughs, and breathes with difficulty, the chest is first examined; with 
another suffering from intestinal disorders, attention is first given to 
the abdomen; in still other instances, the nervous system is first re- 
viewed. Even when a diagnosis appears to have been perfectly deter- 
mined by the examination of one apparatus the rest of the organism 
must always be systematically explored. This is the only way to avoid 
gross errors. 

We shall therefore review the principal rules presiding over clin- 
ical examination. We shall indicate the usual procedures which can 
be utilized by the physician without the aid of any instrument. This 
method of exploration, which is, as a rule, sufficient to lead to diag- 
nosis, may, however, be completed by more delicate procedures ; 
but the latter, requiring special knowledge and highly complicated 
instruments, do not admit of current use in daily practice. They will 
be briefly referred to in the next chapter. 



EXAMINATION OF THE SICK 415 

Examination of the Cikculatoey Apparatus 

The physician may have already been guided to a diagnosis by the 
information furnished by the patient. Paroxysms of dyspnoea, par- 
ticularly of that dyspnoea designated as dyspnoea of effort; presence 
of a slight perimalleolar oedema in the evening ; palpitation, praecordial 
pain, and a phenomenon of far greater importance — i. e., attacks of 
angina pectoris — are the disturbances which draw the physician's 
attention to the heart. The facies of the patient also guides the 
investigation. The special mode of lying, the bluish hue, and the 
throbbing of the jugular veins in a mitral patient have already been 
referred to. 

Examination of the circulatory apparatus must be conducted with 
a strict method. It is well to begin, not with the heart, but with the 
pulse. By means of palpation of the radial and the temporal arteries 
it must first be determined whether arteriosclerosis exists. The beat- 
ings which may involve certain arteries, especially their flexuous rami- 
fications, must be carefully noted. They can be made out by means of 
inspection of the vessels of the elbow joint, temple, and neck. Abrupt 
movements of extension produced at each cardiac systole are observed 
in arteriosclerotics and aortics, and are known as the dance of 
arteries. 

After this first inspection the pulse is felt and its frequency regis- 
tered. Its strength and fulness is determined, and whether it is regu- 
lar and equal. The pulse is irregular when its pulsations are not sepa- 
rated by equal intervals; it is said to be unequal when the successive 
beats do not possess the same intensity or volume. It must also be 
noted whether the pulse is full or compressible. In the former case 
the artery remains sufficiently open after beating; in the latter, it 
empties itself abruptly. A strong but compressible pulse immediately 
suggests an aortic insufficiency (Corrigan's pulse). It is possible to 
exaggerate these characters by raising the patient's arm; it is readily 
understood that the depression consecutive to the cardiac systole is 
thus made more apparent. In such cases the examination must be 
completed by a research of " capillary pulsation/' a name designating 
the alternation of redness and paleness visible in richly vascular parts 
of the body, such as the forehead — after friction is made in order to 
increase the influx of blood — the nails, and the palate. It is well, 
moreover, to feel the various arteries, especially those of the neck, in 
order to note the presence or absence of thrill, which is particularly 
frequent in cases of aortic insufficiency. 

Without dwelling on other peculiarities which may be presented by 
the pulse, we must mention dicrotism. This is the exaggeration of a 



416 INTRODUCTION TO THE STUDY OF MEDICINE 

normal phenomenon — viz., the arterial pulsation is followed by a sec- 
ond slighter shock. 

Examination of the Heart. — After these first inquiries as to the 
state of the circulatory apparatus, examination of the heart is 
taken up. 

Inspection. — It is necessary for the patient to be in the reclining 
posture at the time of this examination. This rule admits of no ex- 
ception. He must lie upon his back, and the physician should place 
himself at his left side, and then take such a position as to bring 
his face down to the level of the patient's thoracic wall. Examin- 
ing the precordial region in this position, he will clearly see, unless the 
subject be obese, under normal conditions, the apex beat, about 2 cen- 
timetres below the nipple. Under pathological conditions the im- 
pulse may be stronger or weaker, and it may even be imperceptible. 
The apex beat may be displaced downward and outward. The precor- 
dial region may present a general vaulting or a limited pre-eminence, 
which may at times be very pronounced and even pulsating, as occurs 
in case of aneurism. In certain instances a more delicate phenomenon 
is observed — viz., the systolic retreat of the apex — indicating a peri- 
cardiac adhesion, and often attended by an undulating movement of 
the precordial region. 

Palpation. — A second mode of examination is represented by pal- 
pation. The intensity and extent of the cardiac impulse and the ex- 
istence of thrilling can be made out by the hand flatly applied to the 
precordial region. Then an exploration is made with one finger with 
a view of determining exactly the point at which the impulse takes 
place, as well as the point of the thrill, should any exist, and, finally, 
the sensitiveness of the organ. Peter has justly laid stress upon the 
importance of the pain which is produced by pressing upon the heart 
in cases of myocarditis or pericarditis. Palpation is mostly resorted 
to for determining the position of the apex beat. One finger is fixed 
at the point where the pulsation is felt, then with the other hand the 
intercostal spaces are counted. In this manner it is learned that, under 
normal conditions and in the reclining position, the apex beat is situ- 
ated at the fourth intercostal space. It is often said simply that it 
beats below the nipple. This point of comparison is very simple and 
convenient, but it is not precise, especially in women, whose mammary 
glands are often distended or hanging; variations are therefore too 
considerable to permit the use of this point of localization. 

Even in the normal state the situation of the apex beat varies with 
the position assumed by the patient. When he lies upon the left 
side, the beat is displaced 2 to 5 centimetres; when he lies upon the 
right side, the point of pulsation is not changed. In the standing 



EXAMINATION OF THE SICK 417 

position it is somewhat lowered and deviates outward. It is likewise 
important to know that in children the apex beat is located 2 or 3 cen- 
timetres outside of the nipple under normal conditions. 

After having determined the place where the shock is produced, its 
intensity should also be noted. In order to accomplish this, the ex- 
aminer must be familiar with the practice of palpation and have pre- 
served the memory of the tactile sensation obtained in normal indi- 
viduals of the same age and nearly the same degree of muscular and 
adipose development as the subject under examination. 

Palpation next informs us as to the cardiac rhythm — that is, as to 
the regularity and equality of the beats. When the beating is irregu- 
lar, it is well to examine simultaneously the heart and the radial 
artery. In fact, a curious discordance between the rhythm of the 
heart and that of the pulse is observed in some cases. False in- 
termittences are said to exist when no cardiac irregularity corre- 
sponds to the radial irregularity; in this instance there is simply 
cardiac inequality; the weakest beats are not transmitted to the 
periphery. 

If palpation is practised with sufficient care, information of the 
first importance is at times acquired for diagnosis. Indeed, it is pos- 
sible to thus perceive murmurs which are too often looked for by 
means of auscultation alone. When the murmur is vibrating, it is 
expressed by a purring tremor readily appreciable by palpation ; if the 
pulse be examined at the same time, it can easily be learned at what 
instant of the cardiac revolution this tremor is produced. It is even 
easier to determine its seat, and palpation renders good service in this 
regard as well, since the murmurs are propagated and auscultation 
always permits location of them as precisely as does palpation. 
Mitral stenosis especially may be diagnosticated without the aid of 
auscultation. By means of this same procedure certain other phenom- 
ena may also be perceived — for instance, pericardiac frictions and 
often galloping murmur. 

Percussion. — After palpation, percussion is practised, proceeding 
from the sonorous toward the nonsonorous parts. Two zones are thus 
delimited: a peripheral zone, which is dull, and corresponds to that 
portion of the heart which is covered by the lung; and an internal 
zone, triangular in shape and of absolute flatness. The first begins 
from the left border of the sternum, at the lower part of the second 
rib, and is limited by a curved line reaching the apex. The zone of 
flatness begins lower down at the level of the fourth rib, and termi- 
nates also at the apex. The flatness of the lower part of the heart 
is confounded with the flatness of the liver. In order to outline the 
right border of the heart, we must percuss below the right nipple; 



418 INTRODUCTION TO THE STUDY OF MEDICINE 

when the upper limit of the liver is obtained, it must be united to the 
apex by a straight line. Then we must delimit, on the right side of 
the sternum, the dull zone which is produced by the prominence of the 
organ. Finally the aorta is percussed, which normally gives a dulness 
of 2 centimetres on the right side of the sternum. 

Cardiac flatness varies considerably under various pathological con- 
ditions. Without describing the phenomena that may be observed, we 
shall give simply a summary of the principal modifications. 

1. Hypertrophy of the left ventricle : The apex is displaced down- 
ward and thrown outward. The line marking the upper limit of flat- 
ness is raised and passes above the nipple. 

2. Hypertrophy of the right ventricle : The apex beat is pushed 
slightly outward; the line limiting the flatness passes a little above 
the nipple, and there is a notable zone of flatness on the right side of 
the sternum. 

3. Pericardial effusion. 

a. If the fluid is not very abundant, it accumulates in the infero- 
external angle of the pericardium; flatness is found at a point below 
the apex beat. 

b. When the effusion amounts to about 400 grammes, the flatness 
takes a peculiar form, known as flatness in the shape of a coffee-ring 
cake (en brioche) ; at the upper part a quite characteristic notch is 
found (Sibson's notch). 

c. In cases of profuse effusions, flatness is triangular in shape, 
with the base down. The right side of the triangle is less oblique 
than the left. 

Auscultation. — The last and the most important mode of explora- 
tion is auscultation. As the physician must place himself at the left 
side of the patient, he will consequently auscultate with his right ear. 
It is better, however, to acquire the habit of auscultation with either 
ear. Moreover, it is well to feel the pulse of the subject while listen- 
ing to the pulsation of the heart, in order to readily determine the 
time of the cardiac revolution. 

Although it is not an absolute rule, it is preferable to begin aus- 
cultation with the base and explore successively the aortic orifice in 
the right second intercostal space, then the pulmonary orifice in the 
left third intercostal space, the mitral orifice at the apex beat, and 
finally the tricuspid orifice at the xiphoid appendix. 

Two sounds are heard under normal conditions. The first or the 
systolic corresponds to contraction of the ventricles; it is customary 
to represent it by a brief (^). Then comes the brief silence, and 
after this the second or diastolic sound, which coincides with the 
closure of the semilunar valves; this is represented by a long ( — ). 



EXAMINATION OP THE SICK 419 

Finally, another period of silence is produced, that is the long silence, 
after which the movements are repeated. 

The object of listening to a heart is to determine the force of the 
impulse; the relationship between cardiac and arterial pulsations; 
the modifications of rhythm and pitch, and whether any pathological 
murmurs are superadded to or replacing a normal sound. 

In order to appreciate the force of pulsations, one must have lis- 
tened to a great number of healthy hearts. The ear preserves, as it 
were, the memory of the physiological sounds and perceives very ex- 
actly the changes which occur. It should be borne in mind that 
these modifications may vary from one orifice to another. Hence, an 
exaggeration of the second sound is quite frequently met with at the 
pulmonary orifice, indicating nothing more than some disturbance in 
the circulation of the lung. 

Diminution in the intensity of the cardiac sounds may be due to 
several causes. In some instances it depends simply upon the exag- 
gerated obesity of the subject; in others it is referable to weakness 
of the myocardium, and then it is the first sound that grows dull and 
finally disappears. This phenomenon, while very serious, is, however, 
of less gravity than weakness of the second sound. Lastly, the heart 
beats may grow weak and even become imperceptible as the result of 
effusion within the pericardium. In the latter case, when the fluid is 
not too abundant, it is possible to perceive the sounds through a 
stethoscope pressed well upon the chest when the patient is in the sit- 
ting posture with the body inclined a little forward. 

The disturbances of the cardiac rhythm may be divided into two 
groups : intermittence and arrhythmia. 

In case of intermittence the series of pulsations is from time to 
time interrupted by a more or less periodical suspension. The patient 
is not infrequently conscious of these arrests, and justly notices that 
suppression of a beat is followed by a systole of far greater energy. 

Arrhythmia is divided into regular and irregular. The irregular 
comprise: (1) The false steps — i.e., irregularities in the succession 
of heart beats. (2) Chronological perversions characterized by a too 
prolonged duration of some one of the heart beats or of one of the 
periods of silence. Eegular arrhythmia includes (a) the cardiac 
oigeminia and trigeminia — viz., the production of two or three beats 
one after another, followed by a sufficiently long pause; (b) the 
alternating pulse (Traube), characterized by one strong beat followed 
by a weak pulsation, whether bigeminia be present or not; (c) the 
coupled rhythm of the heart, when the cardiac revolutions are coupled, 
so to say, in strokes of two ; the first of the couple is strong, the second 
is so weak that it is not perceptible at the radial artery except when a 



420 INTRODUCTION TO THE STUDY OF MEDICINE 

registering apparatus is employed; (d) lastly, under the name of 
alternating pulse, cases have been recorded by Dr. Bard in which a 
series of strong pulsations is followed by one of weak strokes. 

The cardiac rhythm may also be modified by certain changes occur- 
ring in the relations or intensity of each heart beat. For example, the 
two sounds may become equal, then the duration of the two periods 
of silence, and the pitch as well as the intensity of the two beats be- 
come similar. In this event, the frequency being augmented at the 
same time, the ear perceives exactly the same rhythm as when a foetus 
is auscultated. Hence the name foetal rhythm justly given by Stokes 
to cases of this kind. This phenomenon, which is observed in acute 
myocarditis, possesses great semeiological importance and is of highly 
unfavourable prognostic significance. 

The rhythm may be modified as a result of the decomposition of 
one of the sounds. In most cases it is the second sound that is decom- 
posed. The result is a rhythm with a triple sound made up of one 
brief and two long sounds following each other very closely. This is 
the murmur of recall (bruit de rappel), which may be encountered in 
normal subjects; in this case, however, it is intermittent and transi- 
tory, and is due to the fact that the two sets of semilunar valves do 
not close simultaneously. This is what occurs in pathology when some 
disturbance of the pulmonary circulation modifies the play of the 
valves — e. g., in mitral stenosis. 

In some rare instances — not so rare, however, as most authorities 
believe — the rhythm with three sounds is due to the breaking up of 
the first sound. The author has frequently met with this rhythm 
in auscultating at the base of the xiphoid, but it has been impossible 
to determine its pathological significance. 

Auscultation frequently reveals an additional sound preceding the 
systole; this is the galloping murmur. The superadded sound consti- 
tutes a tactile rather than an auditory phenomenon; it depends upon 
an abrupt distention of the ventricle, whose elastic force has increased 
at the expense of the contractile power. It is therefore readily per- 
ceived by palpation, and it is thus possible to recognise that it pre- 
cedes the first sound and is independent of it. 

The galloping murmur is perceived in two different places. In most 
cases it is a galloping murmur of the left heart, and is heard a little 
inside of and above the apex beat, resulting from alteration of the 
myocardium. It is of very frequent occurrence in sclerosis of the 
heart, and generally accompanies interstitial nephritis. A second 
variety, far less frequent, is the galloping murmur of the right heart, 
which is heard over the xiphoid appendix and indicates gastrointes- i 
tinal, oftener hepatic, disorders, particularly colic of lithiasis. 






EXAMINATION OF THE SICK 421 

The modifications above referred to may easily be represented in a 
schematic manner: 



a) 


v_y 


V^ 


Ky 


v_y 


v_y 


« 


^y 


W 


w 


w 


w 



c) w__ w__ w__ w__ w__ 



/) 



Legend 



Normal rhythm ... a 

Bigeminated rhythm o 

Murmur of recall c 



Decomposition of the first sound. ... d 

Galloping murmur e 

Festal rhythm / 



The rhythm may also be modified by additional murmurs originat- 
ing in the pericardium. These are frictions, the name of which is 
sufficient to indicate the character. They have been compared to the 
murmur produced when paper is crumpled or to the creaking of new 
leather. They may accompany the two movements of the heart or 
one of the two periods of silence. The murmur is, as a rule, one of a 
to-and-fro character. When the friction occupies one of the periods 
of silence it produces a rhythm with three sounds, which must not be 
confounded with the galloping murmur. 

The blowing murmur is comparable to that produced when bellows 
are blown in making a fire (Laennec). The murmur is said to be 
systolic when it covers the first movement of the heart ; diastolic, when 
it accompanies the second; mesosystolic, when it occurs during the 
brief silence; presystolic, when it precedes the first sound; it then 
coincides with the contraction of the auricle, and therefore should be 
called auricular systolic. In case one has not yet become well accus- 
tomed to auscultation, it is better to feel the pulse while listening to 
the heart; the murmurs accompanying the radial pulsation are sys- 
tolic; those which precede it are presystolic; those that follow it are 
mesosystolic. The diastolic murmurs are readily recognised, since 
they accompany the second sound, and are, as a rule, gentle and 
aspiratory. 

The following table shows the relationship existing between the 
various movements of the cardiac revolution and the murmurs that 
are met with : 



422 



INTRODUCTION TO THE STUDY OF MEDICINE 



First Movement. 


Short Silence. 


Second Movement. 


Long Silence. 


Ventricular systole. 

Shock of the apex. 

Radial pulse. 

Systolic blowing 

murmur. 


Mesosystolic blow- 
ing murmur. 


Closure of the 
semilunar valves. 


Diastole, auricular 
systole. 

Presystolic 
murmur. 



The first thing to do is to time and locate the murmur. In doing 
this the stethoscope is often of valuable service. When this is done, 
it is, at least theoretically, quite easy to draw conclusions. It will 
suffice to remember the physiological state of the heart at the moment 
the murmur is produced. 

During the systole the ventricles contract; if the seat of the 
murmur is at one of the auriculo-ventricular orifices, it is because the 
blood flows backward from the ventricle to the auricle; there is then 
insufficient closure, or, as is said, insufficiency or incompetency of one 
of the auriculo-ventricular valves. When the murmur is heard at one 
of the arterial orifices, it indicates that this orifice does not allow the 
blood to pass through it as easily as under normal conditions, this 
being due to diminution of its calibre. Stenosis is then said to exist. 

When the murmur is diastolic and coincides with the second 
sound, it means that the blood flows backward from the arteries into 
the ventricles; there is aortic insufficiency, and, exceptionally, insuf- 
ficiency in the pulmonary artery. The diastolic murmur heard at the 
apex has particular characters; it is a rolling rather than a blowing 
sound. It is produced by stricture of an auriculo-ventricular orifice, 
nearly always of the mitral. The significance of the presystolic mur- 
mur is the same. 

These varieties of murmurs may very readily be understood by 
examining the following table : 



Systolic 



f At the base 



Diastolic 



Presystolic . . ] 



To the right of 
the sternum. 
To the left of 
I the sternum. 

At the apex 

At the xiphoid appendix 

f To the right of 
the sternum. 
To the left of 
the sternum. 

At the apex 

At the xiphoid appendix 

At the apex 

At the xiphoid appendix 



At the base . -{ 



Aortic stenosis. 

Stenosis of the pulmonary 

artery (quite rare). 
Mitral insufficiency. 
Tricuspid insufficiency. 

Aortic insufficiency. 

Pulmonary insufficiency 

(exceptional). 
Mitral stenosis. 
Tricuspid stenosis (rare). 
Mitral stenosis. 
Tricuspid stenosis (rare). 



EXAMINATION OF THE SICK 423 

Without dwelling on the characters of murmurs, we shall only 
recall that the murmur of mitral insufficiency is often a whistling, 
sometimes a musical or piping one. That of aortic insufficiency is 
mild, soft, and blowing. That of mitral stenosis is rather analogous 
to rolling. Finally, a systolic, forcible, vibrating murmur is at times 
heard in the centre of the precordial region, unattended by purring 
tremor; it means inocclusion of the intraventricular septum. In 
this case, and when there is stenosis of the pulmonary orifice, it is 
well to auscultate the back of the patient. Over the fourth dorsal 
vertebra a murmur is heard indicating the persistence of the arterial 
channel; it is due to a lesion of compensation occurring quite fre- 
quently in cases of congenital malformations of the heart. 

When a murmur is found, timed, and located, its propagation 
must then be determined. This is of considerable importance in 
definitely locating the murmurs, and especially for distinguishing 
those due to cardiac lesions from those produced independently of 
any alteration of the heart and which constitute nonorganic mur- 
murs. This distinction is not always easily made; it presents great 
interest, however, for the reason that organic murmurs are signs of 
grave lesions, while nonorganic have no prognostic value. 

Nonorganic murmurs are usually mesosystolic, exceptionally dias- 
tolic or rather mesodiastolic. They are soft, blowing, and superficial ; 
they easily vary from one moment to another; they are best heard at 
the end of inspiration, and disappear at the end of expiration. Tak- 
ing ground on this last character, Professor Potain ascribes to these 
murmurs a pulmonary origin. They are due to the fact that the 
systolic contraction imparts to the anterior border of the lung move- 
ments which cause the expulsion or the aspiration of a certain amount 
of air. According to this pathogenesis, it is comprehensible that these 
murmurs should be heard exclusively in those parts of the heart which 
are in contact with the lungs. In the mitral area the organic and 
the nonorganic murmurs occupy the apex. But whenever a murmur 
is heard either outward or inward from the apex or at the left border 
of the heart, it can be pronounced as nonorganic. Of course organic 
murmurs may be conducted into these regions, but the nonorganic or 
extracardiac murmurs alone are localized therein. In the aortic area 
murmurs are nearly always organic. In the pulmonary area they are 
sometimes organic and at other times nonorganic. The same is true 
along the left border of the sternum and at the ensiform cartilage, 
although in these last two areas nonorganic murmurs very seldom 
occur. 

Extracardiac murmurs are attenuated when the subject takes the 
standing posture ; then, in fact, the heart comes more directly in con- 
28 



424: INTRODUCTION TO THE STUDY OF MEDICINE 

tact with the thoracic wall. For the same reason they likewise disap- 
pear during an effort. If the patient can frequently be auscultated, 
daily modifications are observed, and even disappearances. It must 
also be borne in mind that nonorganic murmurs are incapable of 
propagation. This fact is of great consequence, since organic mur- 
murs present propagations which are very important to know. Mitral 
murmurs, for example, are conducted into the left axilla and are 
heard behind, especially in children, under the angle of the scapula. 
It is therefore necessary that these areas should always be included 
in the auscultatory examination. 

The murmurs of the pulmonary orifice are conducted toward the 
left clavicle; they suddenly stop before reaching this bone. Aortic 
murmurs are extended toward the right clavicle, which they reach 
and often go beyond, since they are still audible in the vessels of the 
neck. In a great number of instances the diastolic murmurs of the 
aortic orifice follow another direction. They are propagated along 
the sternum, from above downward, and are very clearly heard at the 
xiphoid appendix; in certain cases their maximum occupies the apex, 
in others the left portion of the sternum. Notwithstanding the vari- 
ability of localization, interpretation is easy. The murmur of aortic 
incompetency presents special characteristics and is attended by phe- 
nomena which do not permit of error. As already stated, it is a soft, 
blowing murmur, so peculiar that no other lesion can simulate it 
except at times some extracardiac murmur or friction. There are, 
however, manifestations accompanying the murmur which settle" the 
diagnosis : these are a jerking pulse, called Corrigan's pulse, throb- 
bing or dance of the arteries, the intermittent double crural murmur, 
and capillary pulsation. 

In the way of practical conclusion it may be said that ausculta- 
tion at the classic foci is not sufficient ; the propagations of murmurs 
must also be looked for. In order to obtain positive information as 
to the nature and site of murmurs, the ear should be applied to spots 
far removed from the areas where they are produced. Extracardiac 
murmurs are produced and expire on the spot, while intracardiac mur- 
murs are diffuse. Before they can be declared to be organic, apex 
murmurs must be heard in the axilla, and even in the back ; and basic 
murmurs must be conducted through the vessels emanating from the 
affected orifice or along the sternum. 

In case a murmur should be diffuse and is heard at two orifices, 
it is often difficult to tell whether we have to deal with a single mur- 
mur or two different ones. Judgment should be based especially on 
the pitch. When a murmur is heard in one area and is propagated 
to another orifice, still preserving the same acoustic characters, al- 



EXAMINATION OF THE SICK 425 

though weakened, it is possible to affirm with certainty that the lesion 
is single. 

When two differently timed murmurs are heard, it should not be 
hastily concluded that two lesions exist. For instance, a double aortic 
murmur — namely, a systolic followed by a diastolic murmur, does not 
necessarily mean a double aortic lesion — i. e., a stenosis with insuffi- 
ciency. In a great number of instances aortic incompetency is at- 
tended by a systolic murmur which simply depends upon the rough- 
ened condition of the orifice. Finally, when a diastolic blowing mur- 
mur is heard along with a presystolic murmur of the apex, it does 
not necessarily follow that there is aortic insufficiency with mitral 
stenosis. A simple aortic incompetency may give rise to both mur- 
murs. According to Flint, the presystolic murmur is due to the 
vibration of the mitral valves caused by the blood current. According 
to Keyt, it is produced at the beginning of systole. 

Examination of the Peripheral Vessels. — Examination of the cir- 
culatory apparatus is terminated by the study of the peripheral ves- 
sels. As already stated, the pulse must first of all be felt and flex- 
uosities of the arteries looked for. After exploration of the heart the 
condition of the vessels may again be studiejd, if there is reason for 
so doing. If aortic dilatation is suspected, palpation should be prac- 
tised above the clavicles in order to determine whether the sub- 
clavian arteries, particularly that of the right side, are not raised. 
The fingers should be pressed above the manubrium to discover 
whether the dilated aorta is not bulging there. The neck of the 
patient must next be examined to decide whether any arterial pulsa- 
tions, and especially venous pulsations, exist. In the case of tricuspid 
insufficiency, the blood regurgitates into the auricle and vena cava 
during ventricular systole. It thus imparts a series of pulsations to 
the brachiocephalic venous trunks; when the valves supplying these 
veins yield, the blood easily flows back into the jugulars. The latter 
then pulsate like arteries; this is venous pulse. By pressing the 
blood from below upward, it is easy to see that the lower portion 
again becomes full; this minor exploration thus enables the physi- 
cian to conclude as to the unquestionable presence of venous regur- 
gitation. 

Palpation may also reveal the existence of arterial thrill. In cases 
of aortic incompetency a thrill is found particularly in the carotids, 
at times so intense as to first suggest aneurism. 

Furthermore, auscultation of the arteries should not be over- 
looked. Arterial and venous sounds are to be sought for in the neck. 
Arterial murmurs may be due to propagation of some aortic murmur 
or to the presence of an aneurism of the carotid or aorta. Venous 



426 INTRODUCTION TO THE STUDY OF MEDICINE 

murmurs are commonly nonorganic. The most important is that of 
chlorosis; it is a continuous murmur (bruit de (Liable) with systolic 
re-enforcement. 

When aortic incompetency is suspected, the stethoscope must also 
be applied to the femoral artery at the base of Scarpa's triangle. The 
ear there perceives a double murmur, which has been well studied by 
Durozier. 

In brief, the diagnosis of a heart lesion can only be made in a 
precise manner by taking into consideration a whole series of phe- 
nomena. Examination of the heart is not sufficient. This must be 
supplemented by examination of the vessels for the diagnosis and by 
that of various organs for the prognosis. We are thus led to speak 
of the other viscera. The respiratory apparatus will first be con- 
sidered. 

Examination of the Respikatoky Appaeatus 

Labynx. — Examination of the larynx can hardly be made without 
special instruments. It is possible, however, to acquire some infor- 
mation concerning the state of this organ by questioning the patient, 
and especially by interpreting certain functional derangements. 

The patient complains of pains during deglutition; he often suc- 
ceeds in locating them precisely : the trouble is not in the throat, but 
farther below, in the neck, and pressure upon the larynx gives rise 
to painful sensations, which serve to establish the diagnosis. Phona- 
tion is sometimes painful, and always disturbed; the voice does not 
possess its normal quality; it is hoarse, bitonal, or multitonal. At 
a more advanced stage the patient is unable to speak except in a 
whisper. 

The phenomena become complicated when the passage of air is 
hindered by various causes, such as partial destruction with secondary 
vegetating productions, cicatricial stricture, swelling of the mucous 
membrane or subjacent parts, as occurs in the oedema of the glottis, 
formation of pseudo-membranes in croup, and in the presence of a 
foreign body or a polypus. Under these conditions the obstruction of 
the air passage is expressed by a special facies and a series of manifes- 
tations of semeiological importance. Dyspnoea is experienced during 
inspiration; the air penetrates but slowly, often giving rise to a 
hissing murmur, and, particularly in young subjects, to a depression 
above the sternum, known as suprasternal retraction. At the same 
time, especially if the obstacle is very troublesome, each contraction 
of the diaphragm is attended by the formation of a furrow along 
the border of the false ribs; this is called infrasternal retraction. 
These phenomena, which are very striking in diphtheritic laryngitis, 



EXAMINATION OF THE SICK 427 

indicate the necessity of operative intervention — tracheotomy or in- 
tubation. 

A relatively simple examination thus makes evident that the 
dyspnoea depends upon laryngeal alteration. In a great many in- 
stances the signs just described are the only ones to be considered. 
Laryngoscopic examination is useless and even dangerous in a patient 
suffering from asphyxia. Auscultation of the larynx, which reveals 
the so-called flag murmur in case of pseudo-membranes, is a proced- 
ure seldom resorted to. 

Beonchi and Lungs. — When the other parts of the respiratory 
apparatus are in question, attention is directed to their alterations 
by the various symptoms described by the patient. These are pain in 
the side, dyspnoea, cough, and expectoration. 

Subjective Symptoms. — The pain in the side is commonly referable 
to irritation of the intercostal nerve, produced by inflammation of the 
pleura. To enumerate the causes capable of giving rise to this in- 
flammation would be to cite all the affections which attack the pleura 
primarily or secondarily. The principal conditions are pleurisy, pneu- 
mothorax, inflammation of the peripheral parts of the lungs, whatever 
their nature, pneumonia, broncho-pneumonia, gangrene, embolism, or 
tuberculosis. The pain is spontaneous, and is aggravated by move- 
ment and cough ; it is often exasperated by palpation. In certain in- 
stances it irradiates toward the hypochondrium and loins. When 
there is diaphragmatic pleurisy, pain is produced by pressure with the 
finger either over the course of the phrenic nerve, between the scalens, 
or along the left border of the sternum, or else at a point situated at 
the intersection of the prolongation of the sternal border and the 
tenth rib. This is the diaphragmatic button of Gueneau de Mussy. 

Dyspnoea is equally a subjective and an objective phenomenon. The 
patient complains of oppression, and trie physician notes certain 
changes in the respiratory rhythm, to which reference will be made 
in treating of inspection. . 

Cough is an abrupt contraction of the expiratory muscles attended 
by spasm of the constrictors of the glottis. It is a reflex phenomenon 
whose point of origin may be found in the most varied parts of the 
organism — e. g., the external auditory canal, the tonsils, the alimentary 
canal, the liver, and the spleen. In thoracic affections it presents cer- 
tain peculiar characters connected with its origin or the lesion exciting 
it. At times it is dry, as is observed in pleurisy and in the beginning 
of most pulmonary affections. It becomes moist as soon as bronchial 
hypersecretion is produced, and it is then accompanied by expectora- 
tion. Cough may occur in isolated efforts in " spells." In bronchial 
dilatation the patient on awakening rejects by long paroxysms of cough 



428 INTRODUCTION TO THE STUDY OF MEDICINE 

purulent liquids accumulated during the night. In the beginning of 
tuberculosis cough appears in the morning, toward 5 a. m. In whoop- 
ing cough the paroxysmal character is most manifest. There then 
occur several series of coughing separated by a hissing inspiration, all 
ending in the expulsion of a viscous fluid. The name " whooplike " 
(coqueluchoid) has been given to a cough similar to whooping cough, 
but less hissing, and commonly connected with a hypertrophied con- 
dition of the tracheo-bronchial glands. 

Furthermore, according to its acoustic characters, cough may be 
sonorous, hoarse, or hissing. 

Although cough possesses no more than a restricted value from a 
semeiological standpoint, it acquires considerable importance by the 
products which it expels to the exterior. Expectorations must be care- 
fully studied. We shall first consider the results furnished by a simple 
examination with the unaided eye ; in most cases this is the only mode 
of exploration which can be resorted to, and we shall see that it gen- 
erally affords the physician sufficient information. 

Expectorations. — Sputa may be serous, mucoid, seropurulent or 
mucopurulent, or sanguinolent. 

Serous sputa, consisting of a frothy, aerated fluid, are quite rare; 
they are met with in asthmatiform bronchitis of arthritics and in 
cases of so-called albuminous expectoration, which is sometimes ob- 
served in consequence of thoracentesis. 

Expectoration is tenacious and colourless in acute pulmonary con- 
gestion and splenopneumonia. 

Mucoid sputa, consisting of a transparent, glairy, colourless, aer- 
ated, and frothy fluid, expresses simply a bronchial hypersecretion; 
they are observed in bronchitis, at least in the beginning. In tuber- 
cular cases they sometimes contain small purulent particles, and, after 
a paroxysm of asthma, small dry, elastic, and granular masses. 

In plain (lobar) pneumonia the sputa are mucoid, but possess an 
absolutely characteristic appearance : they are viscous, thick, adhering 
to the vessel, and rusty in colour. Their semeiological importance is 
very great for the reason that in central pneumonia, auscultation 
revealing no disorder, they constitute the only certain sign of the 
disease. 

Mucopurulent expectoration is of very frequent occurrence. It is 
observed in the second stage of acute bronchitis, in chronic bronchitis, 
and in tuberculosis. In the last-named disease the sputa have a special 
appearance, on account of which they have been called /nummular 
sputa. They are large round or oval flat masses swimming in a 
mucoid fluid and remaining clearly separated when placed in water. 
This very important expectoration is not, however, absolutely pathog- 



EXAMINATION OF THE SICK 429 

nomonic; it is also found in bronchial dilatation, influenza, and 
measles. 

Mucopurulent expectoration may be coloured by the substances 
inhaled by the patient. Hence it is black in anthracosis and red in 
siderosis. 

Purulent sputa form at the bottom of receptacles a greenish-yellow 
mass having the appearance and odour of pus. They are encountered 
in the last stages of acute bronchitis, influenza, caseous pneumonia, and 
particularly in dilatation of the bronchi. In the morning the patient 
empties his bronchial cavities which were filled during the night. 

In certain instances a patient is seen to suddenly expel a consider- 
able amount of pus through the respiratory passages. This is desig- 
nated as vomique. Three causes may give rise to it. It sometimes 
results from a pulmonary abscess opening into the bronchi, in which 
case the pus is usually thin and reddish ; at other times it is due to the 
opening of a purulent pleurisy, at times occupying the great pleural 
cavity, but in most cases being confined to a limited spot. These are 
generally cases of metapneumonic and especially interlobular pleurisy; 
the pus is quite copious, somewhat thick and greenish. Finally, a 
third variety, more difficult of diagnosis, is represented by those cases 
in which an abscess, formed in a neighbouring region, opens into the 
bronchi; suppurations of the liver, kidneys, and mediastinum, and 
abscess caused by congestion, are the most frequent agencies. 

Expectorations may also contain more or less organized produc- 
tions, such as pseudo-membranes proceeding from the larynx, at times 
from the trachea or bronchi, in some cases presenting a ramified ap- 
pearance, reproducing the ramifications of the respiratory passages. 
These productions are seldom met with in diphtheria, but more fre- 
quently in a type of chronic bronchitis which for this reason is desig- 
nated as pseudo-membranous. 

There may also be found membranes or detritus of hydatids, or 
minute granules of a yellow colour, indicating an actinomycotic focus 
opening into the lungs. 

Finally, expectoration may contain variable quantities of blood, 
under which circumstances it is called hemoptysis. Of this two prin- 
cipal varieties are admitted. At times the blood is red, aerated, and 
frothy, as is the case in hemoptysis of bronchial origin; it is of fre- 
quent occurrence, and is the type encountered in tubercular subjects. 
At other times the blood comes from a pulmonary hemorrhage; an 
infarction, or, in other words, a pulmonary apoplexy, has taken place. 
These sputa, described since the time of Laennec as hemoptoic, are, 
unlike the preceding variety, dark, thick, viscous, and nonaerated; 
they adhere to the walls of the vessel containing them and exhale an 



430 INTRODUCTION TO THE STUDY OF MEDICINE 

acrid odour. This kind of expectoration is observed in cardiac pa- 
tients, particularly in mitral stenosis, in the course of infectious or 
chronic dyscrasias, such as Bright's disease, and as a result of em- 
bolism. 

Bronchial hemoptysis may be sufficiently profuse to cause death; 
it is not, however, prolonged after the occlusion of the vessel from 
which it issued. Pulmonary hemoptysis is less abundant, but it lasts 
several days in succession, since the lungs require a certain length of 
time to rid themselves of the blood infiltrating the parenchyma. 

Not unlike these two varieties is the expectoration having the ap- 
pearance of currant jelly ; it is met with in cases of pulmonary cancer. 

A last advice is to smell expectorations. Their odour possesses 
great semeiological importance, especially in cases of fetid bronchitis 
and pulmonary gangrene. The odour often leads to the diagnosis of 
a sphacelated focus. 

Examination of sputa may be completed by microscopical and bac- 
teriological researches, the principles of which will be referred to in 
connection with diagnosis. 

Physical Signs. — Inquiry into the physical signs is conducted in the 
same manner as in the case of the circulatory apparatus. The general 
appearance of the patient is first noted. The exact number of respira- 
tory movements per minute is registered, and it is often of interest 
to determine the relationship existing between the frequency of respira- 
tion and that of the pulse. Under normal conditions the respiration 
rate is 16 and that of pulse 80 per minute; that is, a ratio of 1.5. It 
is equally easy to make out the amplitude, form, and rhythm of respira- 
tion. The movements may be more or less profound than in health, 
they may also be unequal or irregular. 

In certain instances respiration presents peculiar rhythm, of which 
there are three notable types: 

Cheyne- Stokes respiration is especially observed in cerebral or me- 
ningeal lesions, particularly in tubercular meningitis, as well as in cer- 
tain auto-intoxications, such as uraemia. It is characterized by the 
following rhythm : The respiratory movements are at first rapid and 
superficial, then they become more and more profound; this is fol- 
lowed by a gradual diminution in the amplitude of the movements, 
which are finally arrested; there is apncea for a few seconds and then 
breathing is again resumed, at first hardly perceptible, but becoming 
progressively fuller. These various phenomena thus follow each other 
in regular alternation. 

KussmauVs respiration occurs in diabetic coma. It is characterized 
by an abrupt and deep inspiration, followed by a pause, then by -a 
quick expiration and a new pause. 



EXAMINATION OF THE SICK 431 

These two respiratory types are probably referable to disturbances 
of the medulla; at all events, they are independent of pulmonary 
lesions. With the expiratory breathing of Bouchut we return to our 
subject. This peculiar type of respiration is met with in children suf- 
fering from broncho-pneumonia. It is, as it were, the reverse of the 
normal type. Breathing begins with a brisk expiration, followed im- 
mediately by an inspiration; repose takes place after inspiration in- 
stead of after expiration. 

As already stated, the mode of breathing and the important de- 
formities of the chest are noted by means of inspection. Previous dis- 
eases may have produced deformities which disturb the regular play 
of the lungs and thus favour alterations of this organ. Pott's disease 
and rickets often cause extensive deviations in the form of the thorax. 
In other instances the defective conformation results from occupa- 
tions which necessitate certain movements or certain attitudes. These 
facts are not without importance, but they act only as predispos- 
ing causes. 

Deformities connected with alterations of the respiratory apparatus 
may be general or partial. 

General deformities occur under two principal forms. 

In emphysema the lungs, having become too voluminous, give rise 
to dilatation of the thorax. The chest is rounded and, in advanced 
cases, is deservedly called "barrel-shaped." The sternum is pushed 
forward, the intercostal spaces are no longer visible, the supraclavicu- 
lar depressions disappear, the neck is shortened, and the head appears 
to be borne directly upon the shoulders. 

The consumptive's appearance is just the reverse of the preceding. 
The chest seems to be elongated, the eminences are more apparent 
than in health, the interspaces are more conspicuous, the scapulae are 
protruding, and the muscles atrophied. If a slight percussion is 
practised, fibrillary contractions (myoidema) appear beneath the skin 
covering the muscles, especially the pectoral muscles. 

The partial deformities of the chest consist in bulgings and re- 
tractions. 

In tumours of the mediastinum and in pleural effusions, one half 
of the thorax is increased in size; it sometimes assumes a rounded 
shape and imparts to the chest the appearance described as oblique 
oval. In order to well appreciate these deformities the following pro- 
cedure may be resorted to : One end of a string is held by a finger at 
the upper part of the sternum at equal distance from both clavicles; 
the lower end is then brought to the pubis. Under normal conditions 
the string divides the anterior part of the thorax into two equal halves ; 
it therefore traverses the middle of the sternum. In case of effusion 



432 INTRODUCTION TO THE STUDY OF MEDICINE 

or tumour, the point of the sternum is deviated toward the diseased 
side, and the deviation to one side of the middle line measures the 
degree of deformity. 

Instead of bearing on one side of the chest, as in the example above 
described, the deformity may be local and express a more extended 
tumefaction. Such is notably the case with purulent pleurisies. The 
impulse of the heart is sometimes transmitted to this tumefaction, 
thus constituting the pulsatile empyema which may be mistaken for 
an aneurism. 

Certain functional derangements disturb the expansion of the 
thorax. As a result of intense pain or of some inflammatory lesion 
in the neighbourhood of the diaphragm, the breathing becomes far 
less deep upon one side than upon the other ; it may even be arrested 
on the affected side, resulting in manifest asymmetry during inspi- 
ration. 

Partial deformities may consist in retractions. In cases of chronic 
pleurisy the persisting adhesions give rise to retraction of the dis- 
eased side. Laennec has laid great stress on this type of alterations, 
of which he has given a figure that has become classical. 

These various alterations of the thorax sometimes produce skin 
lesions. When there is exaggerated expansion the skin cracks and 
presents vibices, which persist for an indefinite period and at times 
serve for retrospective diagnosis. 

Finally, examination of the integument may reveal oedema of the 
thoracic wall, an important phenomenon, for, in case of pleurisy, it 
is a sign pointing to the purulent character of the collection. Less 
frequently a subcutaneous emphysema is found due to the presence of 
gas bullae proceeding from some minor fissure in the respiratory ap- 
paratus. 

The results afforded by inspection should be completed by mensu- 
ration. It is possible to obtain important information by means of 
bimanual palpation. The patient being in the sitting posture, one 
hand is applied to the anterior part of the chest, the other to the pos- 
terior; in this manner the expansion is appreciated by the separation 
of the arms from each other. By examining alternately each half of 
the thorax and by seating one's self successively to the right and to 
the left of the patient, the deformities and expansion of each half 
may be determined with a little practice. 

A procedure which is as simple as but more exact than the pre- 
ceding consists in measuring each half of the chest with a centimetre 
measure, or even with a string. One end of the string being fixed 
at the spinous apophyses, the other end is brought to the middle 
of the sternum. In thus taking the measure, the modifications of 



EXAMINATION OF THE SICK 433 

the thorax produced by breathing must, of course, be noted, and 
the degree of expansion at the end of inspiration and expiration 
registered. 

Palpation. — Palpation practised with the hand flatly applied to 
the thorax at times reveals friction and rales. When there is abundant 
pleural collection it is possible to feel with the hands the fluctuation 
in an intercostal space. Palpation may also appreciate the beating 
and reducibility of certain tumours. 

Palpation is particularly useful in recognising vocal fremitus. The 
patient is ordered to count aloud, and the physician, carrying his hands 
successively over all parts of the thorax, appreciates the intensity of 
vibrations, which may be increased, lessened, or absent. The changes 
are better noted when the two sides are compared. Increase in vocal 
fremitus indicates increased density of the pulmonary parenchyma; 
the phenomenon is therefore produced in case of compression, intense 
congestion, hepatization, and tubercular induration. Diminution of 
fremitus means that the parenchyma is rarefied, as occurs in emphy- 
sema, and especially that the lungs are abnormally separated from the 
chest wall; therefore fremitus is weak or altogether absent when the 
pleura is thickened, and particularly when there is liquid or gas in 
the sac. This research is one of great semeiological importance, for it 
serves to differentiate pneumonia from pleurisy and pneumothorax 
from a cavity. 

Percussion. — After palpation, percussion is practised. Care should 
be taken to percuss from the apex of the chest downward, first in 
front and then behind, one side and then the other, and, moreover, 
to compare the two sides in percussing the homologous parts. It must 
be remembered, however, that sonority is not the same everywhere, 
even under normal conditions. On the right side there is an area of 
hepatic flatness appreciable behind and still more so in front, where 
it begins at the fifth rib and becomes absolute below the sixth. 

The modifications of sound revealed by percussion consist in in- 
crease or diminution of sonority. In the former case tympanism is 
said to exist; in the latter, flatness. 

Tympanism may be general, unilateral, or partial. When general, 
it corresponds to a permanent distention of the air cells — viz., to em- 
physema. It is unilateral especially in pneumothorax. When partial, 
it indicates a limited pneumothorax, or that the subjacent portion of 
the lung is pushed away and compressed. Hence, in case of pleural 
effusion and at times even of pneumonia, a tympanitic sound is often 
heard beneath the clavicle, designated as Skodism, in honour of a 
Vienna physician, Skoda, who demonstrated it. 

Flatness may occupy a more or less extensive portion of one lung 



434: INTRODUCTION TO THE STUDY OF MEDICINE 

or of both lungs. It varies in intensity. When it is very slight, as 
occurs in certain cases of tuberculosis, dulness is said to exist. Flat- 
ness is very obvious in pneumonia and is absolute in pleurisy. 

Certain areas should be percussed with special care. These are 
the infraclavicular regions and the supraspinous fossae. Dulness at 
the apex is, in fact, of great semeiological importance, since it is one 
of the principal signs of pulmonary tuberculosis. 

A very careful percussion should be made over the roots of the 
bronchi in children. The ganglia located there, being often increased 
in size, give rise to flatness. 

Finally, in the anterior and lower part of the left side, there is a 
semilunar space known as Traube's space, presenting tympanitic reso- 
nance with high pitch, due to the presence of the stomach. This 
space becomes flat on percussion in cases of very copious pleural 
effusion. 

Care should always be taken to percuss during the two movements 
of breathing, directing the patient to open and close his mouth, and 
to sit down or stand up. In fact, it is readily understood that the 
tone should be more tympanitic during inspiration, for a greater 
amount of air is at this time present in the lungs. When the mouth 
is open, resonance increases; when it is closed, it diminishes. 
These modifications of resonance are supposed to possess diagnostic 
value in distinguishing a cavity from a pneumothorax ; but, in reality, 
the differences are not constant. 

In case of large cavities, the separate strokes of percussion below 
the clavicle elicit a peculiar sound, called cracked-pot sound (bruit de 
pot fele), which results from sudden compression of the air. This 
phenomenon is produced only when the mouth is open ; it disappears 
after several percussions, to reappear after a deep inspiration. 

It must also be remembered that the position of the patient modi- 
fies the results of percussion. The pitch is lower in the sitting tnan 
in the lying posture of the subject. 

All these somewhat dry details are indispensable, since in a great 
many instances the differences appreciated by percussion are minute 
and have no value except when exploration is performed under well- 
determined conditions. 

Auscultation. — Although percussion is very useful, auscultation 
affords information of greater certainty. 

Auscultation, like percussion, should also be made from above 
downward, and the corresponding regions of the two sides compared. 
The points to be noted are the intensity and tone of the respiration, 
the relative duration of its various cycles, and in certain instances' 
the superadded murmurs. 



EXAMINATION OF THE SICK 435 

The breathing may be more intense than normally ; then it is des- 
ignated as puerile, for respiration is more active in children than in 
adults. It may be hardly perceptible or not all over a more or less 
extensive region: this is respiratory silence (pleurisy with copious 
effusion, massive pneumonia). 

Modifications in pitch are very numerous. They are described as 
rude or harsh, humming or jerking, which terms sufficiently indicate 
their stethoscopic characters. 

Finally, the relative duration of the various respiratory phases 
•may also have been modified; notably expiration may become longer 
than inspiration. 

These various modifications, though quite slight on the whole, 
acquire great importance in certain instances. Humming respiration, 
coinciding with exaggerated resonance on percussion, is a sure sign 
of emphysema. A jerking respiration with a prolonged expiration 
below the clavicle indicates incipient tuberculosis. 

Superadded murmurs are of far greater importance. They are 
resolvable into frictions, which take place in the pleura, and rales, 
which are produced in the trachea, bronchi, or lungs. 

It is not always an easy matter to distinguish frictions from rales. 
It is well to recall that frictions are more superficial and less regular, 
are generally heard at both phases of the breathing, and are not modi- 
fied by cough. Their intensity and pitch are variable. At times they 
are slight and mild, similar to the murmur produced by the crushing 
of tissue paper; on other occasions they are intense, recalling the 
noise made by new leather. Their presence justifies the physician in 
diagnosticating a dry pleurisy. 

Bales are resolvable into three groups: dry or sonorous rales, 
crepitant rales, and moist rales. 

Dry or sonorous rales are called rattling when they have a grave 
pitch, and sibilant when acute. They are frequently intermingled 
and may coexist with a variety of sonorous rales resembling the cluck- 
ing of the hen. They indicate bronchial inflammation or catarrh. 

The crepitant rale is similar to the noise produced by throwing a 
little salt into fire; it may more exactly be obtained by taking a 
lock of hair between the thumb and finger and twisting it before the 
ear. This sort of rale is heard during or rather at the end of inspira- 
tion, and is characteristic of pneumonia. 

Laennee described under the name of crepitant rale of resolution 
that sound which is audible at the third stage of pneumonia. It is 
clearly different from crepitant rale in that it is larger and moister 
and is commonly produced in both phases of the breathing. It is a 
subcrepitant rale. 



436 INTRODUCTION TO THE STUDY OF MEDICINE 

Moist rales are divided, according to their size, into rales with 
gross bubbles, with bubbles of medium size, and with small bubbles. 

Bales with gross bubbles, or mucous rales, are met with in bronchitis, 
in bronchiectasis, and in chronic pulmonary congestion. Rales with 
bubbles of medium size, or subcrepitant rales, are heard when the inflam- 
matory process reaches the bronchi of middle calibre. Rales with fine 
bubbles signify capillary bronchitis, a focus of congestion, or incipient 
broncho-pneumonia. When located at the apex, they constitute a reli- 
able sign of tuberculosis. When bubbling rales are mixed with sono- 
rous or sibilant rales, a tempestuous murmur (bruit de tempete) is said 
to exist. 

Cavernous is called a bubbling rale which gives to the ear the sen- 
sation of resonance in a cavity. 

Unequal, irregular, dry, or moist murmurs are often heard at the 
apices, known as crackling. When dry, they are symptomatic of a be- 
ginning tuberculosis; when moist, they are connected with softening 
of the lesions. 

There is blowing when the respiratory murmur is replaced by a 
sound more or less analogous to that which is heard on auscultation 
over the trachea or the roots of the bronchi. This stethoscopic phe- 
nomenon is due to condensation of the pulmonary parenchyma, which 
transmits to the ear the murmur produced in the adjacent healthy 
parts. The blowing is called bronchial when it is similar to that heard 
on auscultation of the bronchi. It is said to be tubal when it has a 
slightly metallic character. These various murmurs, whose qualities 
are very variable, may be well fixed in the ears by the following prac- 
tice: The hands are united in the shape of an ear trumpet and 
through them the vowels a, e, o, or the diphthong ou, are pronounced 
in a low, blowing voice. By further narrowing the trumpet thus 
formed and pronouncing the vowel i, a different murmur is produced, 
which is analogous to the pleuritic blowing murmur. 

The pleuritic murmur is a tubal blowing murmur transmitted from 
the bronchi to the ear through the lung compressed by the pleural 
effusion. The interposition of a liquid layer modifies the quality of 
the sound; the murmur becomes soft, as if veiled or produced at a 
distance from the ear. It is not absolutely distinctive of pleurisy, 
since it also occurs in certain pulmonary congestions, particularly in 
Grancher's spleno-pneumonia. 

As to the bronchial murmur, it simply indicates increased density 
of the lung. It occurs under the most varied circumstances — e. g., 
pneumonia, broncho-pneumonia, pulmonary congestion, caseous 
masses, tumours, and sclerosis. 

A murmur may be due, not to the transmission of a normal sound, 



EXAMINATION OF THE SICK 437 

but to the production of a superadded one in some dilated or exca- 
vated portion of the respiratory apparatus. When dilatation is not 
considerable, a murmur similar to bronchial murmur is still heard, as 
is the case in dilatation of the bronchi. When, however, there is a 
large excavation, the cavernous or, at a more advanced degree, the 
amphoric murmur is met with. The former of these may be produced 
by blowing through the hands widely separated, the latter by blowing 
into a bottle with a large neck. 

The cavernous or gurgling murmur is symptomatic of excavation, 
without, however, prejudging the pathological nature of the latter. 
It may be found in bronchial dilatation as well as in gangrene or 
abscess of the lungs, and by preference in tubercular cavities. It is 
often combined with moist rales which possess the same quality, and 
are designated, according to their size, as cavernular, or cavernous. 
When the rales are numerous and varied gurgling is said to exist. 

The amphoric murmur, which at times originates in a vast cavity, 
is encountered especially in pneumothorax. In conjunction with it an 
additional murmur is very often heard, analogous to that which would 
be produced by grains of sand falling into a metallic cup: this is 
Laennec's metallic tinkling, due to the resonance produced through the 
layer of air by the fine rales in the lungs. The metallic tinkling 
should not be confounded with Trousseau's brassy murmur (bruit 
d'aurain). In percussing with one coin upon another flatly placed 
upon the anterior wall of the chest, a metallic sound is heard by 
auscultation of the posterior wall, which sound appears to be pro- 
duced just under the listening ear. This is Trousseau's murmur of 
brass. Finally, as with air there is commonly associated a more or 
less considerable amount of liquid, it is possible, by shaking the pa- 
tient, to hear a hydro-aerial noise similar to that produced when a 
half -filled bottle is agitated : this is Hippocratic succussion. 

Lastly, the voice and the cough must be auscultated. 

The patient should be instructed to speak aloud while the physi- 
cian is auscultating. Sonorous syllables must by preference be pro- 
nounced. It is customary to tell him to count, beginning with 30, or 
to repeat the figure 33. The voice assumes the same quality as the 
murmur. Should a sharp and tremulous pleuritic murmur exist, the 
voice will also arrive at the ear with the same characters: this is 
egophony. This phenomenon is almost pathognomonic of pleurisy or 
of spleno-pneumonia ; it is often more clearly heard than the blowing 
murmur. In cases in which bronchial or cavernous murmur is pres- 
ent, the voice partakes of the bronchial or cavernous quality. 

Moreover, the whisper of the patient is in some instances per- 
ceived by auscultation as clearly as though the patient were speaking 



438 INTRODUCTION TO THE STUDY OF MEDICINE 

into the ear: this is called aphonous pectoriloquy, which is mostly ob- 
served in serous pleurisy. 

Those above indicated are the principal physical signs to be looked 
for in cases of pulmonary affections. In order to diagnosticate well, 
one must consider all the phenomena observed, coordinate and group 
them, and also take into account not only their characters but their 
locations. For instance, localization at the apex is an important 
sign of tuberculosis. Furthermore, the mobility of certain phenom- 
ena should not be overlooked. The stethoscopic signs are apt to vary 
considerably from one moment to another in uncomplicated bron- 
chitis, particularly in pulmonary congestion, and at times in broncho- 
pneumonia. 

Not including emphysema and the rare lesions of the lungs, we 
can easily represent in tabular form (page 439) the diverse physical 
signs which enable the physician to make a differential diagnosis of 
thoracic diseases. It is of course to be remembered that the diag- 
nosis is not possible unless the subjective disturbances, expectoration, 
general phenomena, and especially the course of the events are duly 
taken into consideration along with the physical signs. 

Examination - of the Digestive Canal 

Examination of the alimentary tract must be made from above 
downward, beginning with the lips, teeth, tongue, and throat. Very 
little can generally be learned from observation of the lips, and what 
little information is obtained is not connected with the condition of 
the digestive organs. It will suffice, therefore, to recall here the dry- 
ness of'the lips in grave infections, the trembling observed in a great 
number of nervous diseases (the most remarkable type of which occurs 
in general paralysis), the eruptions, such as herpes, which are pro- 
duced in fevers, the bluish colour of cardiac patients, etc. 

Examination of the teeth is of greater interest. In children, the 
delayed appearance of the teeth is dependent upon nutritive derange- 
ments. Their erosions and notches are symptomatic of rickets and 
hereditary syphilis. In the case of syphilis a lesion of great semeio- 
logical bearing is frequently observed, consisting in a peculiar form of 
the upper incisors, to which reference is already made under the des- 
ignation of Hutchinson's tooth (page 228). 

Dental caries possesses considerable importance; it sometimes ex- 
plains digestive disturbances. Many dyspeptics have been cured by 
having their teeth taken care of, or by using artificial teeth. On the 
other hand, premature decay of the teeth is often referable to nutritive 
disorders. In diabetes, for example, the second lower molars are 
affected and their alteration serves as a guide to the diagnosis. Prema- 



EXAMINATION OF THE SICK 



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440 INTRODUCTION TO THE STUDY OF MEDICINE 

ture loss of the teeth must also be taken into consideration, since 
it reveals failing nutrition, and at times a nervous affection, such as 
locomotor ataxia. 

Dental alterations often coexist with gingival lesions. The state 
of the gums should therefore be noted; they may be ulcerated or 
covered with a pultaceous exudate. When saturnine intoxication is 
suspected, examination of the gums is of great consequence, since the 
bluish line at the insertion of the teeth is absolutely characteristic. 

Examination of the mouth is completed by that of the cheeks, where 
not infrequently are found ulcerations, pustules, and pigmentary spots, 
as occurs in Addison's disease. At the corners of the mouth are ob- 
served nacreous patches, called smokers' patches. 

Examination of the Tongue. — The appearance of the tongue is of 
greater interest. In cases of digestive disorders, especially an attack 
of indigestion, the tongue is large, bearing the impression of the teeth, 
and often covered with a whitish or yellowish coating. It is dry in 
grave fevers, and becomes covered with a fuliginous, dark coating. 

In certain diseases the appearance of the tongue is sufficiently 
peculiar to acquire a certain diagnostic value. In typhoid patients it 
is white in the middle and red on the borders. In influenza, according 
to Dr. Faisans, it presents the appearance of porcelain. Its examina- 
tion is of especial service in scarlatina. When the eruption has disap- 
peared or is not clearly marked, the diagnosis is made dependent upon 
the state of the tongue, whose mucous membrane, deprived of the 
epithelium, presents a set of papillae of a deep red or raspberry colour. 

Of the other alterations of the tongue we shall mention the pig- 
mentary modifications and slaty patches of Addison's disease, the black 
deposits of parasitic origin, the desquamations in areas (marginate 
exfoliating glossitis, geographical tongue), which were unjustly attrib- 
uted by Parrot to syphilis; the patches of tobacco smokers, and the 
white, corneous patches designated as leucoplasia or lingual psoria- 
sis, which are unimportant of themselves, but are often transformed, 
in the course of a few years, into epithelioma. 

Finally, ulcerations may be met with in the tongue. Some of them 
are simply caused by dental lesions ; others are referable to some acute 
infection or to intoxication ; and others are produced by syphilis, tuber- 
culosis, and cancer. 

The modifications of the saliva are more important. The secretion 
is diminished in acute infections and in certain poisonings (bella- 
donna) ; in certain other poisonings it is increased (pilocarpine), in 
buccal inflammations, notably in gingivites, mercurial or ulcero-mem- 
branous stomatitis, in certain nervous diseases, and especially in dys- 
pepsia. In the last-mentioned case the saliva, abundantly produced, 



EXAMINATION OF THE SICK 441 

is swallowed during the night and accumulates in the stomach; in the 
morning, on awakening, the patient has a pituita whose salivary char- 
acter is demonstrated by the presence of potassium sulphocyanide, 
tested by perchloride of iron. 

The breath should not be overlooked, for it is often fetid, either by 
reason of increased fermentation in the alimentary canal, or owing 
to the presence of putrefactive lesions in the mouth or throat, or 
sphacelus in the bronchi or lungs. The volatile products which develop 
under the influence of microbes are absorbed and eliminated by the 
lungs as well as by the skin. 

Examination of the Throat. — Examination of the throat, which is 
made simply by depressing the tongue with the handle of a spoon, 
should never be overlooked, especially in children. 

The patient facing the light, the physician examines the palate, 
the uvula, the pillars, the vault of the pharynx, and the tonsils, care 
being taken to press the tongue well down when looking at the tonsils 
in order to get a view of their lower part. The motility of the soft 
palate and uvula, the colour and development of the various parts, the 
presence of ulceration and false membranes must be noted. In cer- 
tain cases it is necessary to introduce the index or, better, two fingers 
into the mouth in order to determine whether a tonsillar ulceration 
represents an indurated chancre, or whether a pharyngeal tumefac- 
tion is due to a fluctuating abscess. 

Throat inflammations assume two principal appearances. In some 
instances the mucous membrane is red, without any whitish exudate, 
as is the case with simple sore throat, either idiopathic or symptomatic, 
and at times with phlegmonous angina. In other instances the mucous 
membrane is covered with a whitish deposit. When the exudate is 
thick, slightly greenish-white in colour, adherent to the mucous mem- 
brane, uniformly spread, occupying both tonsils and invading adjacent 
parts, especially the uvula, then diphtheria must immediately be 
thought of. The moderate febrile reaction, the swollen glands, and, in 
some cases, the edematous tumefaction of the neck, the bad general 
state, and the paleness of the skin further help to establish the diag- 
nosis of diphtheria. On the other hand, diphtheria is excluded when 
the exudate is white and limited to the tonsils, presenting small 
rounded patches disseminated in the tonsillar crypts, and attended by 
a sudden and intense rise of temperature, while the general state re- 
mains tolerably good. Then cryptic, herpetic, or simple membranous 
sore throat is said to exist. Finally, angina is called pultaceous when 
the exudate is thick, creamy, and loosely adherent. 

There are also ulcerating and gangrenous anginas, but they are 
quite uncommon. 



442 INTRODUCTION TO THE STUDY OF MEDICINE 

The differential diagnosis of anginas gives rise to serious difficul- 
ties. In fact, the following questions must be answered : Is the angina 
catarrhal, phlegmonous, pseudo-membranous, gangrenous, or ulcerat- 
ing? Is it primary, or symptomatic of rheumatism, of erysipelas, or 
of mumps? Is it one that occurs in the beginning of eruptive 
fevers — i. e., measles, scarlatina, or smallpox ? Is it a syphilitic an- 
gina? If a primary angina, what is its nature? Especially when 
pseudo-membranes are present, is the case one of diphtheria? 

We can not sum up here, not even briefly, the differential characters 
indicated by authorities. Despite the minutest observations a great 
many clinicians at the present day believe that the diagnosis of anginas 
is impossible without the assistance of bacteriology. There is in this 
assertion one of those exaggerations of which the history of medicine 
furnishes so many examples. In the majority of cases the diagnosis 
can be made with a tolerable degree of certainty to satisfy the require- 
ments of a rational treatment. However, in order to be able to make 
a clinical differentiation one must have examined a considerable num- 
ber of angina cases and acquired an experience demanding far longer 
study than the bacteriological research of Loeffler's bacillus. 

Examination of the Esophagus. — The lesions of the esophagus may 
give rise to marked disturbances of deglutition. An organic stricture 
or a reflex spasm produced by an ulceration, or compression exerted 
by a neighbouring tumour, especially by an aneurism of the aorta, 
causes the arrest of the alimentary bolus or its rejection by regurgi- 
tation or vomiting. In milder cases there is only a sensation of 
constriction. 

The cervical part of the esophagus may be examined by palpation, 
which permits detection of tumefaction produced by accumulation of 
aliments in those cases in which the stricture is situated high enough. 

Percussion exceptionally reveals an area of flatness at the sides of 
the spine. Gurgling in the dilated portions may be heard by ausculta- 
tion. If the patient swallows water, it may be noted by means of 
auscultation that the noise which is normally heard all along the 
esophagus is not audible below the point of stricture. 

All these procedures are generally insufficient. A more complicated 
examination and the use of catheterism are nearly always required in 
order to arrive at a positive diagnosis. 

Examination of the Stomach and Intestine. — The digestive canal — 
viz., the stomach and intestine — is the source of disturbances which are 
as numerous as they are varied. As always, examination must first be 
guided by interrogation in the following manner : 

The patient should be asked whether his appetite has increased, 
diminished, or been perverted, or whether he experiences disgust for 



EXAMINATION OF THE SICK 443 

certain foods. In case of cancer of the stomach, the patient has an 
invincible disgust for meat. 

He must next be questioned whether certain aliments or certain 
condiments render his digestion more troublesome. The influence of 
acid foods and those containing vinegar should particularly be in- 
quired into. 

Then the sensations experienced after meals should be noted. Dis- 
turbances may appear immediately or some time after taking food. 
Sometimes even before the end of a meal the disorders appear, such as 
a sense of discomfort and fulness, at times pain, or even vomiting. In 
other instances the trouble is felt from one to four hours after taking 
food. The symptoms are divisible into two main groups. There may 
be slow digestion with a sense of fulness and swelling. This is the 
hypohydrochloric type. Or there may be intense or even very violent 
pain, often in the form of cramps. This is the type of hyperacidity — 
i. e., there is excess of hydrochloric acid in the stomach. In order to 
confirm the diagnosis sodium bicarbonate should be administered at 
the time of pain. The hydrochloric acid thus being saturated by the 
base, eructations of carbonic acid are produced and the pain vanishes 
in a few minutes. 

Then inquiry is made as to the other gastric phenomena. It .should 
be learned whether the patient has morning pituite — which is so com- 
mon in catarrhal gastritis, especially when it is of alcoholic origin — 
regurgitations, vomiting, or eructation; and in case the answer be 
affirmative, their characters, notably their odour, should be carefully 
ascertained. Then follows an inquiry into the condition of the intes- 
tine — whether there is constipation or diarrhoea, and what are the 
characters of the faecal matter. Finally, the associated phenomena, 
especially the nervous manifestations, should be considered — e. g., 
headache, congestion of the face, somnolence after meals, insomnia 
during the night, a tired feeling, often more marked in the morning 
on awakening than in the evening, and inaptitude for work, all of 
which are symptoms of great importance. 

Vomiting. — The vomited matters must be examined with particular 
care. Their quantity, consistence, and odour are at least approxi- 
matively noted. Their reaction is generally acid; it is alkaline in 
cases of catarrh and cholera. Then the variety of vomiting should 
be determined. Vomiting may be aqueous, alimentary, bilious, faecal, 
hemorrhagic, or purulent. 

Aqueous vomiting is represented by a colourless liquid, which is 
often viscid and ropy as a result of the presence of mucus or swal- 
lowed saliva. It is commonly observed in the morning in cases of 
alcoholic gastritis (pituita), ulcer, cancer of the stomach, in pyrosis, 



444 INTRODUCTION TO THE STUDY OF MEDICINE 

and in cholera, where the vomited substances are remarkable for their 
resemblance to rice water. 

Alimentary vomiting consists of foods and beverages more or less 
digested but still recognisable. This is the most common variety. Not 
infrequently the aliments are mixed with bile. When the latter is 
copious, it imparts to them an intensely green colour. These bilious 
vomitings are often observed in acute gastroenteritis, and especially 
in peritonitis. 

Vomiting is said to be faecal or faecaloid when consisting of sub- 
stances in appearance similar to those found in the intestine. This 
variety is of considerable semeiological importance; it is diagnostic 
of intestinal obstruction. 

Vomiting of blood, or hematemesis, presents itself under two ap- 
pearances. Sometimes the blood is red, sometimes dark, comparable 
to soot or coffee dregs. In the latter case the blood has sojourned in 
the stomach and been partly digested by the gastric juice. Dark- 
blood vomiting points decidedly to the existence of cancer; vomiting 
of red blood is observed in cases of ulcerating gastritis, and especially 
in simple gastric ulcer. 

Finally, examination of vomited matters may reveal therein the 
presence of foreign bodies or parasites, notably ascarides. To this 
reference will be made in connection with microscopical examination. 

The manner in which vomitings occur should also be taken into 
consideration. They may be preceded by nausea and attended by effort, 
as is the case with gastric vomiting. At other times they are pro- 
duced after meals, occasioned by a particularly troublesome paroxysm 
of coughing, such as occurs in consumptives and in those suffering 
from whooping cough. Vomiting may sometimes take place by simple 
regurgitation without giving rise to any sense of discomfort. It is 
very important to be familiar with this variety ; it is observed in cases 
of cerebral or meningeal lesions. 

Faecal Matters. — To appreciate the modifications of foecal matters 
is no less important than the study of the varieties of vomiting. 
Under normal conditions a man evacuates daily 120 to 180 grammes 
of faeces, of a tolerably firm consistence and cylindrical form, of 
brown colour and very slightly putrid odour. They may therefore 
become modified in amount, character, form, colour, and odour. 

The quantity diminishes in certain cases of incomplete constipa- 
tion. Evacuation does take place, but less abundantly. The individual 
has from time to time copious evacuations which empty the bowels. 

The consistence of the matters may also be increased or diminished. 
When hard, their form is also modified : they are at times reduced to 
small round masses, at others to thin ribbons, and also as though 



EXAMINATION OF THE SICK 445 

passed through a wire-drawing plate — pipe-stem faeces. The latter is 
observed in cases of rectal stricture. 

When the consistence is lessened, the matters are either simply 
pasty, or liquid, containing or not solid particles. Since diarrhoea is 
generally dependent upon increased intestinal putrefaction, the matters 
exhale an extremely fetid odour. This is not, however, true of all 
cases ; in cholera the dejecta are odourless. 

Whether diarrhoea be present or not, the colour of faecal matters 
may have been profoundly modified. 

In the first place, the influence of diet should be noted. In infants 
who take milk only, the appearance is that of a gold-yellow paste. 
When an adult is placed upon a milk diet and digestion is quite satis- 
factory, the faeces are dark in colour, hard in consistence, and in small 
rounded masses. As soon, however, as digestion becomes disturbed 
they acquire the nature of infantile faeces : they assume a pasty, yellow, 
or even whitish character. 

The stools are colourless when the bile no longer contains pigment 
(Hanot's pigmentary acholia), and especially when it ceases to now 
into the digestive canal. Hence the necessity of inquiring into, or 
rather personally examining, the state of the faecal matters whenever 
hepatic disorders exist. The condition of the biliary passages is evi- 
denced by the stools being coloured or colourless; in cases of icterus 
the colour shows whether there is polycholia or retention of bile. 

The stools may be mixed with blood. The latter, as in the case of 
vomiting, appears under two forms: at times it is red, mixed or un- 
combined with excrement. In other instances it appears in the shape 
of blackish flocculi, comparable to coffee dregs; then melcena is said 
to exist. 

The red blood, except when it is very abundant, proceeds from the 
lower portions of the large intestine or the anus. It is, therefore, 
necessary in such cases to carefully examine the anal orifice, and, by 
means of inspection and touch, to look for hemorrhoids. 

Black blood may proceed from the stomach; it then makes its ap- 
pearance in consequence of a hematemesis: otherwise it is referable 
to some intestinal alteration, some ulcerating process the nature of 
which should be determined in accordance with the other phenomena 
observed. 

Melcena should not be confounded with the black colour produced 
by certain medicaments. In individuals who have ingested metallic 
salts which form insoluble black sulphides in contact with the sulphu- 
retted hydrogen of the intestine, the stools assume a very dark colour. 
This occurs particularly after the ingestion of subnitrate of bismuth. 

The colour of the alvine discharges is still more profoundly modi- 



446 INTRODUCTION TO THE STUDY OF MEDICINE 

fied in cases of diarrhoea. In simple enteritis the colour is light brown, 
whitish or greenish yellow. In typhoid fever the evacuations are of 
a yellowish colour and nauseous odour. In catarrh of the large intes- 
tine they are made up of a yellowish liquid mixed with mucus; and 
the patient often expels, after a colic, small viscous masses of a rusty 
colour, recalling somewhat the expectoration of pneumonia. At a 
more advanced stage he expels true masses of glairy substance mixed 
or not with false membranes. This is particularly observed in dysen- 
tery: the patient each time evacuates very small amounts of slimy, 
reddish matters mixed with blood and fragments of mucous mem- 
brane; their discharge is attended by rectal tenesmus and often by 
dysuria. 

There is another variety which consists of aqueous, colourless, diar- 
rheal matters containing ricelike epithelial debris. The best-known 
example of this is seen in cholera. 

Finally, the stools, while as a rule diarrhoeal, may present a 
whitish colour due to the presence of a great amount of fat. Fatty 
stools are of great diagnostic value; they indicate that the pancreatic 
juice no longer flows into the intestine. 

Examination of faeces also reveals the presence of substances which 
are not normally met with. 

Alimentary residue, at times even aliments which are discharged 
undigested, may be found in the stools. This phenomenon, designated 
as lientery, is symptomatic of an extensive alteration of the digestive 
mucous membrane, or of a fistula which, establishing a communication 
between two portions of the intestine far removed from each other, 
deprives part of the aliments of the action of the digestive juices. 

There may also be found anomalous productions in the faeces — e. g., 
solid bodies — which, when voluminous, are readily perceived. If they 
are of small size they must be looked for by first throwing them upon 
a sieve and then placing them under a current of water. The sub- 
stances will pass through the meshes and in the residue, apart from 
alimentary debris, will be found stony productions. Some of these 
have the appearance of sand and gravels and proceed from the intes- 
tine itself. Others have originated in the biliary passages, and are 
called hepatic calculi, easily recognisable by their yellow or green 
colour, smooth and polished surfaces, slight density, and high percent- 
age of cholesterine. 

False membranes, often found in the faeces mixed with mucus, 
occur under the form of lamellae and ribbons, which are not infre- 
quently confounded with taenia, and at times under the appearance of 
ramified tubes. The presence of these productions, due to desquama-, 
tion of the mucous membrane, is of great semeiological value. It is 



EXAMINATION OF THE SICK 447 

symptomatic of an intestinal affection extremely difficult of treat- 
ment — viz., muco-membranous enteritis. 

Excrements frequently contain parasites. In most cases the patient 
himself finds them accidentally and reports to the physician. The lat- 
ter must first verify the parasitic nature of the parasite. In this con- 
nection error is not uncommon. Pseudo-membranous fragments and 
even poorly digested aliments have been mistaken for worms. The 
nature of the worm is next to be determined. The ascarides are read- 
ily recognised. The ribbonlike worms present a series of characters 
indicated in every treatise on natural history, which readily permit of 
their recognition. 

Finally, in a great number of instances the study of the dis- 
charges must be completed by a microscopical examination, in order 
to see things invisible to the naked eye — e. g., alimentary debris, 
parasites, and spores of bacteria. 

Examination of the Stomach. — After having concluded question- 
ing of the sick and examination of the excreta, consideration of the 
physical signs must be taken up, beginning with the stomach, con- 
tinuing with the intestine, and ending with the glands annexed to 
the digestive tube. 

Inspection. — In examining a stomach it is best always to begin 
with inspection, which reveals various deformities, which have been 
well studied by Dr. Hayem. 

Deformities may be produced by the corset. There are three 
varieties of them. In some cases compression is suprahepatic, in con- 
sequence of which the organs are pushed downward. There is visceral 
ptosis. In other instances compression bears upon the liver and 
a strangulation is the result, the mark of which is found at the 
autopsy. Compression may also be inf rahepatic ; then, the viscera 
being pushed into the thorax, dyspnoea and, especially, palpitation 
are produced. 

Apart from these particular, cases, the patient facing the physi- 
cian, four varieties of deformity may be seen : ( 1 ) An upper enlarge- 
ment, occurring in great eaters; (2) an enlargement of the lower 
parts of the abdomen, which is met with in debilitated individuals, 
in women who have had several pregnancies, and in patients suffering 
from visceroptosis; (3) a median bulging, connected with gastric 
dilatation; and (4) a flattening of the epigastric region with a bulg- 
ing of the hypogastrium, which indicate dilated stomach with de- 
pressed organs. 

When the patient is turned to one side three deformities are 
noticed: (1) A substernal depression, depending upon an exagger- 
ated vacuity of the stomach and observed in cases of inanition or after 



448 INTRODUCTION TO THE STUDY OF MEDICINE 

repeated vomiting; (2) an epigastric bulging, connected with disten- 
tion of the stomach; and (3) a subumbilical flattening with hypo- 
gastric protrusion, characteristic of visceroptosis. 

Palpation. — Palpation, following inspection, recognises the sensi- 
tiveness of the viscera, and whether any of them have become painful 
or enlarged. Certain precautions, however, should be taken. The 
patient must lie upon the back, the head being very slightly raised, 
the mouth open, the thighs flexed, and breathe forcibly. The physician 
must warm his hands if they are cold; without this precaution, reflex 
contractions would be produced in the abdominal muscles, embarrass- 
ing the examination. Seating himself to the left of the patient, the 
examiner makes several little strokes with the three middle fingers held 
close together and slightly curved. In this manner two things are 
perceived — an auditory sound, called clapotage, comparable to that 
obtained by shaking a bladder half filled with water, and a tactile 
sensation, a shock of return. 

A normal stomach should not give the murmur of clapotage six 
hours after meals, and when it is full of food the murmur in ques- 
tion should not be audible except over an extent of about 2 inches 
below the false ribs. The eliciting of clapotage during fasting may 
be negative even if there is dilatation, for the reason that the stom- 
ach is empty. It will then suffice to cause the patient to swallow a 
small amount of liquid for the distention to become apparent. It 
may be made more manifest if he be directed to drink a little Seltzer 
water. 

It has justly been objected that this inquiry into clapotage ex- 
poses to certain errors. For example, a dilated transverse colon gives 
analogous murmurs. But the clapotage of the colon is heard far- 
ther below and is nearly always obtained in the adjacent parts of the 
ascending and descending colon. In this manner the course of the 
large intestine can be outlined and the clapotage distinguished from 
that of the stomach. 

Palpation also furnishes other information. For example, the 
cancerous tumours of the stomach, at least those of the pylorus and 
greater curvature, can be felt by this mode of exploration, to which 
the tumours of the cardia and lesser curvature are not accessible. 
Moreover, in case there is simply a cancerous infiltration, a diffuse 
induration can be felt. The presence of tumefaction, however, does 
not necessarily indicate the existence of a cancerous growth. Non- 
cancerous indurations of the pylorus are not absolutely rare, espe- 
cially in the aged. Likewise, the borders of a gastric ulcer may be 
indurated and impart the sensation of a tumour, but the other symp- 
toms are sufficiently different to permit of an easy diagnosis. 



EXAMINATION OF THE SICK 449 

Percussion. — Percussion must be made lightly, with one finger at 
least below the false ribs. Above them more strength can be used. 
By this means a tympanitic space (Traube's semilunar space) is made 
out on the left side; its upper limit is represented by a line starting 
from the left border of the sternum, at the fifth interspace, and con- 
tinuing in this space as far as the mammary region. From this point 
the line descends to the seventh rib at the level of the nipple and ter- 
minates at the eighth rib on the axillary line. 

The lower limit evidently varies according as the stomach is 
empty or full. The sonority of an empty stomach is not heard beyond 
two or three fingers' breadth from the costal border; after meals it 
may be perceived at two fingers' breadth above the navel. The sono- 
rous zone measures 10 to 14 centimetres from above downward ; trans- 
versely, 18 to 21 centimetres. On the left it is limited by the splenic 
flatness and below by the tympany of the intestine, the quality of 
whose tone is quite different from that of the stomach. 

Auscultation. — Auscultation of the stomach is of little conse- 
quence. The patient complains of anomalous noises; in the even- 
ing, when he is in the lying posture, he hears a glou-glou in his stom- 
ach on turning to one side or the other. These noises are of two 
kinds. Some are produced in an irregular manner and are due to gas- 
tric contractions; others are rhythmical, and are heard in the stand- 
ing posture in women whose corsets are too tight. Dr. Hayem ex- 
plains this by the .bilobal shape of the stomach, and supposes that the 
gas passes from one pouch to the other with each respiratory move- 
ment. 

Examination of the Intestine. — Examination of the intestine fol- 
lows that of the stomach and is made nearly in the same manner. 
However, inspection renders but little service, except in cases of intes- 
tinal obstruction, when accumulation of gas above the obstacle pro- 
duces partial deformities which point out the site of the lesion. 

Palpation is resorted to in most cases. The painful points are first 
looked for. The most important is that of McBurney, indicative of 
appendicitis; it is seated at the middle of a line extending from the 
navel to the anterior-superior iliac spine : it is the point correspond- 
ing to the insertion of the vermiform appendix upon the caecum. 

In cases of muco-membranous colitis the pains are periumbilical, 
or they occupy the right iliac fossa and the angles of the colon ; while 
in dysentery they are felt in the left flank, extending as far as the 
anus. 

Palpation also detects tumours and indurations of the intestine, 
and the presence of scybala, which in cases of chronic constipation 
may be hard enough to simulate a true tumour. This mode of ex- 



450 INTRODUCTION TO THE STUDY OF MEDICINE 

ploration is of very great importance in cases of obstruction and, 
especially, invagination, as it is possible to feel the sausagelike por- 
tion of the intestine, particularly in children. 

There is an affection called enteroptosis, study of which is made 
by means of abdominal palpation. This morbid state is characterized 
by the prolapse not only of the intestine, but of all the abdominal vis- 
cera. Their means of support have become insufficient, and conse- 
quently all are displaced downward. 

Glenard, who has made a remarkable study of this morbid state, 
thinks that a great number of gastric dilatations should be consid- 
ered as cases of gastroptosis. It is therefore necessary to carefully 
look for organoptosis whenever gastric dilatation is observed. When 
such is the case, a hard cord is perceived above the navel, extending 
transversely. This is the colonic cord of the colon, which can readily 
be pushed upward, but which resists an attempt to push it downward ; 
if force is used, it slides and ceases to be palpable. In the left side 
the cord of the ilium can be rolled under the finger; it lies parallel 
to the Fallopian arch; on the right side a compact and hard mass is 
felt, which is the caecum full of faecal matters, since most persons 
affected with enteroptosis are victims of habitual constipation. By 
continuing the palpation it is possible to determine, by proced- 
ures later to be described, that the liver is lowered, and that the 
right kidney has left its position and protrudes below the epigastric 
region. 

The coexistence of renal ectopia and gastric dilatation has long 
been noted. Bartels thought that the displaced kidney compressed 
the duodenum, and thus obstructing the course of the contents, caused 
a dilatation above the point of compression. According to Bouchard, 
dilatation of the stomach is primary; it produces congestion in the 
liver, and this organ, assisted by a corset or a belt, pushes the kidney 
out of its normal position. Glenard assumes that a laxity of liga- 
ments exists; he argues that the right colonic angle only is affected 
first, and that the kidney is subsequently drawn out by it. 

Finally, there is a mode of exploration which renders some service 
in the diagnosis of visceral ptosis. In case the patient is attacked 
with abdominal suffering, in order to relieve him it will suffice to 
raise up the viscera. To this effect, the subject is instructed to assume 
the upright position; the physician stands behind him, and, pressing 
above the pubis, with his two hands joined at an angle, he pushes 
the viscera from below upward: this procedure produces immediate 
relief. Exploration is then complete; all that is needed is to pre- 
scribe a belt which will compress in the same manner and tend to 
bring the organs to their normal position. 



EXAMINATION OF THE SICK 451 

Examination of the Peritoneum. — The palpation practised for the 
intestine recognises at the same time the state of the peritoneum. 
The inflammatory lesions of the serous membrane, or even of the 
organs covered by it, increase its sensitiveness considerably. Palpa- 
tion then becomes painful and gives rise to reflex contractions, a sort 
of defensive movement, in the abdominal muscles. This phenomenon 
is an important sign of peritonitis, appendicitis, and, in case of trau- 
matism, should suggest a visceral lesion. 

The acute or subacute inflammations of the peritoneum may like- 
wise be very painful. In tubercular peritonitis palpation is generally 
very troublesome. In some instances, however, after having strongly 
compressed the wall, the hand must be removed abruptly in order to 
arouse pain. Finally, it is well to know that even acute peritonitis 
may be painless, and without any appreciable local reaction. In such 
cases acquaintance with the antecedent history and a minute study of 
concomitant manifestations will enable the physician to arrive at a 
diagnosis. 

In chronic, and especially in tubercular peritonitis, palpation re- 
veals hard or resisting parts and pasty masses, and at times it fur- 
nishes peculiar sensations compared to the sound produced by crunch- 
ing snow. Finally, it reveals the presence of a hard cord extending 
from one side to the other of the abdomen across the navel ; this is the 
great omentum infiltrated and retracted. 

In rarer cases of peritoneal cancer an infiltrated mass or a set of 
small separate tumours, at times movable, escaping under the pressure 
of the fingers, are met with. This examination is sometimes rendered 
difficult by the presence of a peritoneal effusion. 

It is readily understood that ascites causes distention of the 
abdominal cavity. If the walls are resistant, it produces an anterior 
protrusion, further exaggerated at times by the prominence of the 
umbilicus. Later on the walls yield and the fluid accumulates in the 
sides of the abdomen. Inspection thus reveals a deformity which be- 
comes almost characteristic when dilated veins appear upon the ab- 
dominal wall, indicating obstruction of the deeper circulation. In 
order to establish with certainty the existence of fluid, percussion is 
'resorted to, which elicits flatness in the lower portions, where the 
liquid has accumulated. When the patient is lying upon his back, a 
zone of flatness is found across the median line, on both sides of the 
abdomen, limited above by a tympanitic line with a superior concav- 
ity. The patient being instructed to alternately lie on the right and 
on the left side, the liquid is easily displaced, except when it is en- 
cysted by pseudo-membranes. It is well, however, to be acquainted 
with the fact that, even in cases of abundant ascites, a sonorous zone 



452 INTRODUCTION TO THE STUDY OF MEDICINE 

is nearly always found in the posterior parts of the flanks, which is 
due to presence of the colon. 

When the liquid is not copious the patient is advised to lie upon 
one side or to assume the knee-chest position; accumulation then 
takes place in the flank or at the umbilical level, and is expressed by 
absolute dulness. 

The data of percussion are completed by looking for the succus- 
sion wave. The patient lying upon his back, the palm of one hand is 
placed on the side of the abdomen, and, tapping lightly with the 
fingers on the opposite side, waves are produced. Care should be 
taken, however, to prevent the transmission of the vibrations of the 
walls by having an assistant place the radial edge of his hand verti- 
cally on the median line while percussion is made. 

It is very important also to discover whether the fluid is free or 
encysted. For this purpose the patient must be percussed in various 
postures. It must be noted whether the fluid flows from one side 
to the other when the patient turns upon his side. It follows the 
laws of gravity if it is free, whereas, if encysted, it presents no modi- 
fication. The same exploration, completed by digital examination of 
the vagina, leads to the differential diagnosis between ascites and an 
ovarian cyst. In the latter case a liquid tumour exists, but it is situ- 
ated laterally and can not be displaced, and it is furthermore limited 
by a line with inferior concavity. 

The state of the mesenteric glands may also be examined by pal- 
pation. In children their tumefaction is particularly easy to appre- 
ciate, especially when they are invaded by tuberculosis. This affection 
was formerly designated as carreau or tabes mesenterica. 

Finally, arterial pulsations are often perceived by palpation in 
the epigastric region, somewhat to the left of the median line. 
The patient sometimes calls the physician's attention to this point; 
he experiences palpitation in the stomach. Does this sensation 
depend upon dilatation of the aorta? It is natural to suppose so, 
for the pulsations are very superficial and auscultation often recog- 
nises there an intense diastolic murmur.* This symptom, which 
is mostly encountered in dyspeptic patients, and in those suffer- 
ing from chronic enteritis and neurasthenia, should be well under- 
stood in order to avoid being led to the diagnosis of aneurism of 
the aorta or of the cceliac axis. This error is avoided by examin- 
ing the patient several days in succession. These arterial palpita- 
tions vary from one day to another, and the physical signs to 

* The diastolic arterial murmurs are those produced during the dilatation of 
the vessel ; they therefore correspond to the cardiac systole or, more exactly, they 
follow it very closely. 



EXAMINATION OF THE SICK 453 

which they give rise are correspondingly modified with the digestive 
disorders. 

In abdominal exploration palpation renders the greatest service. 
Percussion reveals the state of the large intestine, whose tympanitic 
sound differs from that afforded by the stomach or the small intes- 
tine. It also serves to reveal the presence of abdominal tumours and 
intraperitoneal effusions. As to the role of auscultation, it is a lim- 
ited one : it does no more than recognise certain intestinal murmurs 
or peritoneal frictions. ' 

Examination- of the Liver. — Examination of the abdomen 
should be completed by that of the liver, spleen, pancreas, and 
kidneys. 

Hypertrophy of the liver may be appreciable to mere inspection. 
A vaulting is noticed in the right hypochondriac region. When hyper- 
trophy of the spleen coexists, as is not infrequently the case, then a 
tumefaction of the upper half of the abdomen is observed, especially 
in the standing posture. It should be borne in mind, however, that 
the liver is relatively far more developed in children than in adults, 
and even in a normal state causes a certain degree of vaulting. 

In order to exactly determine the volume of the liver, both per- 
cussion and palpation must be resorted to. The patient being upon 
his back, the legs and thighs well flexed so that the abdominal mus- 
cles are relaxed, the physician places himself to the right and pal- 
pates from below upward and feels the lower border of the gland. 

Percussion affords better information. It is made from above 
downward, and often it suffices to percuss on the nipple line; under 
normal conditions absolute flatness begins two fingers' breadth below 
the nipple and terminates at the costal border. The liver is therefore 
considered as prolapsed when its flatness begins and ends below these 
limits, and as hypertrophied when the upper limit of flatness is nor- 
mal or raised and the inferior limit is lowered. These rules will often 
suffice. It is well, however, to be more precise and determine the 
whole extent of the flat zone. The upper limit is normally repre- 
sented by a line beginning at the right border of the sternum, at the 
level of the sixth costal cartilage; it follows the sixth rib to the 
right mammary line, reaches the seventh rib on the axillary line, the 
ninth on the scapular line, and terminates near the spine at the level 
of the eleventh rib. 

While strong percussion is needed to determine the upper limit 
of the liver, light percussion will suffice to mark out the lower limit. 
Without this precaution hepatic flatness would be masked by the 
sonority of subjacent organs. 

Normally, the lower limit of the liver is confounded behind with 



454 INTRODUCTION TO THE STUDY OF MEDICINE 

renal flatness : on the scapular and axillary lines it corresponds to 
the eleventh rib; then it follows the costal border, at equal distance 
from the ensiform cartilage and the umbilicus, and terminates on the 
left side at the level of the apex of the heart. 

There are conditions under which hepatic flatness diminishes while 
the dimensions of the organ are normal. This occurs, for example, 
when there is pulmonary emphysema, gastrointestinal tympany, or 
when the intestine is pushed up by ascitic effusion. 

Atrophy of the liver is observed in various morbid states, especially 
in atrophic cirrhoses, and in that morbid process designated in France 
by the clinical name icterus gravis, and in Germany by the name acute 
yellow atrophy. 

Hypertrophy of the liver may be general or partial. It is general 
in biliary hypertrophic cirrhosis, in alcoholic hypertrophic cirrhosis, 
in fatty hypertrophic cirrhosis, and in the liver of heart disease 
and of amyloid degeneration. It is partial in cases of tumours, 
cancer, and hydatid cyst. Certain portions of the liver may atrophy 
while certain others become hypertrophic; this is observed particu- 
larly in syphilis. It is an important fact that partial hypertrophies 
of the liver are far more frequent than is believed. In a great many 
cases of cirrhosis one part of the gland develops to such proportions 
that the idea of an hydatid cyst is suggested. In not a few such 
instances laparotomy has been performed, and not until after the 
abdomen had been opened was the error recognised. 

When the limits of hypertrophy of the liver have been exactly 
recognised by percussion, palpation must again be resorted to. The 
inferior border must once more be explored to determine whether it 
is sharp or rounded, resistant or soft. The surface must be exam- 
ined with special attention in order to feel the small granulations 
in cirrhosis, and the voluminous nodes in case of cancer. Finally, 
inequalities, prominences, depressions, and fissures are perceived in 
syphilis; hence the characteristic name of foie ficele (liver tied with 
twine) given to this alteration. 

At other times a fluctuating tumour is felt, referable to a super- 
ficial hydatid cyst, and in certain rare instances a peculiar vibration 
is perceived by light percussion, which is known as hydatid thrill or 
fremitus. 

Palpation sometimes appreciates pulsations isochronous with the 
pulse. In some cases they are nothing more than pulsations trans- 
mitted by the aorta. In other instances there is total dilatation of 
the organ, due to backward flowing of the blood at each ventricular 
systole. This is what is called the hepatic pulse, indicated by Senac, 
well studied by Friedrich, and especially by Mahot. This phenome- 



EXAMINATION OF THE SICK 455 

non, which is observed in cardiac patients at the stage of asystole, 
is to be sought for in the following manner: The palm of one hand 
is placed upon one side of the liver, the other on the opposite side; 
it is possible to thus perceive that the beatings are not transmitted; 
at each cardiac systole the liver becomes distended and pushes the 
two hands apart. 

Exploration of the liver is not completed until the gall bladder is 
also examined. When it is distended, it is readily felt to the right of 
the rectus abdominis as a spherical or elongated tumour with resist- 
ant and hard walls, as if calcified. This biliary tumour is at times 
observed in lithiasis — less frequently, however, than might be sup- 
posed, since the cholecyst soon atrophies. The distention is more 
remarkable in an affection of difficult diagnosis — viz., cancer of the 
head of the pancreas. The patient is attacked by a jaundice which, 
as a rule, grows worse, or at least never recedes. At the same time 
emaciation and digestive disturbances are observed, and a character- 
istic hard tumour is revealed on palpation in the place of the gall 
bladder. If, moreover, the faecal discharges, which are colourless in 
all cases of jaundice, are very rich in fat, cancer of the caput of the 
pancreas may confidently be diagnosticated. At any rate, aside from 
cyst of the pancreas, this is the only disease of this gland recognisable 
by our procedures of investigation. 

Examination of the Spleen. — The main procedure applicable 
to the exploration of the spleen is percussion. It is made along a 
vertical line extending from the axilla to the left anterior-superior 
spine of the ilium. Under normal conditions the zone of absolute 
dulness extends from the eleventh rib to the lower border of the 
ninth and presents a length of about 5 centimetres. Splenic flatness 
is confounded posteriorly with that of the kidney. 

In cases of considerable hypertrophy the spleen is appreciable not 
only to percussion, but also to inspection, and still better to palpa- 
tion. This last mode of exploration also reveals the consistence of the 
organ, and the fluctuation observed in cysts and abscesses, as well as 
the unevenness of surface encountered in cancer. 

Auscultation, which is of little importance in abdominal affections 
and serves only for the detection of peritoneal frictions, sometimes re- 
veals a systolic murmur in cases of splenic hypertrophy. 

Examination of the Ukinaey Appaeatus 

Subjective Symptoms. — The first part of the examination of the 

urinary apparatus also consists in interrogation of the patient. The 

phenomena of pain are first to be inquired into, then the manner of 

micturition, and, lastly, the character of the urine is to be determined. 

30 



456 INTRODUCTION TO THE STUDY OF MEDICINE 

Pain is felt in the lumbar and vesical regions. Lumbar pain is 
connected with lesions of the kidneys, the pelves, or ureters, and in 
most cases irradiates to the bladder. The pain may be dull and con- 
tinual, or intermittent and paroxysmal. 

Vesical pains are felt during micturition, and are especially 
marked when the last drops of urine are expelled, whereas, in case of 
urethral inflammation, the first drops give rise to the phenomenon 
of pain. It is also to be remembered that there may be renal or vesi- 
cal pain without any alteration in the urinary passages. Such is the 
case with a great number of nervous diseases. Furthermore, if not 
pain, at least a certain burning is experienced during micturition 
when the urine is concentrated. 

Apart from pain, disturbances of sensation in the urinary passage 
may be observed, dependent upon nervous diseases. In locomotor 
ataxia the patient does not feel the need of micturition; he satisfies 
this function by reason only, as he understands that the call must be 
attended to at certain intervals. Finally, in certain instances the 
urine is voided without causing any sensation, and, if the subject 
does not look at it, he does not know that he is urinating. 

Some patients are otherwise annoyed. They frequently feel like 
passing water and are compelled to satisfy this feeling at very short 
intervals. This trouble may be of a nervous origin, or may be con- 
nected with an inflammation which renders the bladder irritable and 
prevents it from becoming distended; it may also be dependent upon 
a chronic nephritis. It is well to add that pollalciuria, or frequent 
desire to micturate, is not necessarily associated with polyuria, or in- 
creased quantity of the urine. 

The manner of micturition is also to be considered. The patient 
should be questioned whether he easily passes water and whether the 
jet has preserved its normal power; whether the length of the stream 
has not for some time been diminished; whether the liquid, at its 
issue from the urethra, is not divided into two jets or is not twisted, 
and whether, after micturition, he does not wet himself by a few drops 
of urine flowing an instant after. These various changes in micturi- 
tion are highly important from a semeiological standpoint, as they 
point to urethral stricture. In certain instances the flow of urine 
is suddenly interrupted as the result of a transitory obstruction caused 
by a calculus. 

Finally, two other and far more troublesome disturbances con- 
sist in the impossibility of emptying the bladder, or of retaining the 
urine, known respectively as retention and incontinence. Eetention of 
urine is different from anuria. The former is characterized by lack 
of excretion and consequent distention of the bladder by retained 



EXAMINATION OF THE SICK 457 

urine; whereas in case of anuria secretion is suppressed, and the 
bladder is therefore empty. 

Examination of the Urine. — The patient is often aware of the 
quantitative variations of his urine ; he recognises polyuria more par- 
ticularly, which necessitates frequent and copious micturition, even 
during the night. The patient should, nevertheless, from time to time 
be instructed to collect all his urine passed in twenty-four hours. 
According as the quantity is found to be below or above 1,200 to 
1,500 grammes, oliguria or polyuria respectively is said to exist. 

Clinically, examination of the urine is of serious import. In 
order, however, to obtain useful information from this source, exami- 
nation must be made by means of certain reagents. It is absolutely 
necessary to look at least for albumen and sugar. This analysis will 
be referred to in connection with the clinical application of scientific 
procedures. It will suffice here to indicate simply those modifications 
which can be recognised without the assistance of apparatus. 

The odour, density, colour, transparency, and sediments of the 
urine, as well as its quantity, must be noted. 

Normal urine has a peculiar well-known odour. Under patho- 
logical conditions the odour may become ammoniacal, which indicates 
a process of intravesical fermentation. Faecal odour is due to the 
existence of a vesicorectal fistula establishing a communication be- 
tween the rectum and the bladder. In diabetes the urine, like the 
breath, may often assume an aromatic odour, recalling that of chloro- 
form. This phenomenon is of high diagnostic importance, since it is 
one of the first symptoms of the grave state already detailed as dia- 
cetemic coma (page 208). It is also to be remembered that the urine 
may present various odours after administration of drugs — e. g., oil 
of turpentine imparts to it an odour of violet. 

The consistency of the urine is often modified; it is sometimes 
very fluid, sometimes thick, ropy, and viscid. It may very easily 
become frothy; then albumen must be suspected and sought for. 
Finally, it may fall upon the clothing and leave a deposit of glucose. 
It is well to know that this deposit attracts flies, and when these 
insects are seen to assemble in great numbers upon the trousers and 
shoes as soon as the patient lays them aside, diabetes should immedi- 
ately suggest itself. 

The variations in the colour of urine are highly important. It may 
be very pale, as is particularly, the case when the amount of urine is 
increased in diabetes, interstitial nephritis, nervous polyuria, and at 
the time of urinary crises. 

The colour is deep under reverse conditions, as realized by most 
of the infectious diseases, in which instances the urine is scanty, 



458 INTRODUCTION TO THE STUDY OF MEDICINE 

reddish, and sometimes brown. In this last case the colour is gener- 
ally due to the presence of urobilin, which may be recognised by 
spectroscopic examination. 

If the colour of the urine is intensely red, the presence of blood, 
or at least hemoglobin, must be thought of. The spectroscope reveals 
the latter substance, and the microscope the red blood corpuscles. 
When the urine contains blood, the origin of the latter must be dis- 
covered. In women, menstrual blood is mixed with the urine; it is 
easy to avoid error in this connection. If the hemorrhage occurs 
within the urethra, it generally continues, even when no urine is 
passed; at all events it colours but the first drops of urine. It is 
therefore well to instruct the patient to pass urine in several recep- 
tacles, and then to make a comparative examination of the several 
specimens. In cases of renal hemorrhage the blood is, as a rule, more 
copious and is more uniformly mixed with the urine. When there 
is a lesion in the pelvis or ureters, fibrinous casts are commonly found 
moulded in these parts. Vesical hemorrhage is characterized by the 
fact that the blood comes at the end of micturition with the last 
drops of the urine. 

Instead of being red, a bloody urine may present a brown hue as a 
result of transformation of its colouring matter. It is then difficult 
to differentiate it from icteric urine; in such cases Gmelin's test, 
which will subsequently be mentioned, should be resorted to. 

When questioning can not elicit the desired information, recourse 
is to be had to certain simple tests to determine whether the colour 
of the urine is due to the elimination of some medicine. Carbolic 
acid, for example, imparts to the secretion a blackish-brown colour; 
logwood, senna, and rhubarb colour it red; santonin renders it green- 
ish yellow. Finally, the urine of patients affected with melanotic 
tumours presents a black colour, especially when it remains for a few 
hours in contact with the air. 

Instead of being clear and limpid, urine is white when it contains 
emulsified fat (chyluria) or pus. In the latter case a mass of viscous 
consistence is deposited at the bottom of the vessel containing the 
urine. 

A urine which is limpid at the time of voiding may produce a 
deposit when it cools. The sediment may consist of mucus in floc- 
culent masses, or of urates which, after clouding the liquid, subside 
in the shape of a red or rosy sediment. In other instances oxalates 
or phosphates are found; the latter are dissolved by acetic acid. 
It sometimes happens that these various mineral salts are deposited 
within the bladder and are discharged as minute calculi, passage 
of which through the urethra is generally attended by intense pain. 



EXAMINATION OF THE SICK 459 

Apart from the deposits above indicated, the urine often contains 
urethral filaments which occur, as a rule, in individuals having a his- 
tory of gonorrhoea. In certain cases it may even contain tissue 
debris, caseous products, and parasites proceeding from the urinary 
organs or even from the digestive passages. 

We can not enlarge upon all these points, notwithstanding their 
great diagnostic value. The study of the urine, in reality, should 
never be passed over; it affords the physician indications of the high- 
est importance. 

Examination of the Kidney. — Examination of the urinary appa- 
ratus must begin with the kidneys. First of all the region is in- 
spected. The patient should lie upon his abdomen, and in difficult 
cases he should assume a posture in which the light falls upon him 
from before backward. The physician, seated behind the patient, will 
then be able to appreciate whatever depressions and eminences exist. 
The subject should then be directed to turn upon his side, when a 
zone of absolute dulness, extending toward the axillary line, and per- 
haps beyond it, will be found on percussion. The information fur- 
nished by this mode of exploration, however, is far less important 
than that obtainable by palpation. 

The subject lies on his back, the abdomen relaxed by flexion of 
the thighs and legs, and the physician places himself on that side 
which he wishes to examine. He first makes a bimanual explora- 
tion: he places one hand posteriorly upon the loins, while the 
other is applied anteriorly. By gradually pressing with the hand 
in front, and in doing so profiting by each expiratory movement, 
it is possible to palpate the kidney, at least when it is enlarged or 
has become movable; it is then readily sent from one hand to the 
other. In some rare cases resistance and even fluctuation can be 
appreciated. 

In case of renal ectopia Glenard advises depression of the abdom- 
inal wall with the hand placed below the ninth rib. The other hand 
lays hold of the lateral part of the abdomen so as to squeeze it be- 
tween the thumb and medius. The hand thus placed may, at a 
given moment, seize the kidney, which is being pushed toward it. 

It is often a difficult task to find the kidney when the organ forms 
an enormous tumour protruding at the umbilicus and compressing 
the adjacent organs. It may even occupy one entire side of the abdo- 
men, as occurs in cases of hydronephrosis, cancer, and sarcoma of the 
kidney, of such frequent occurrence in children. 

Examination of the Bladder. — The bladder is explored by palpa- 
tion and percussion above the pubis. When it is distended by urine, 
it is felt as a globular, hard, and absolutely dull mass. In this man- 



460 INTRODUCTION TO THE STUDY OF MEDICINE 

ner certain tumours may be perceived. But the examination must 
then be completed by a rectal or vaginal palpation, which alone per- 
mits exploration of its fundus. 

Examination of the Genital Appakatus 

We shall not dwell upon the examination of the genital apparatus, 
which is subject to a somewhat particular technic. We shall confine 
ourselves to indicating the main points. 

In mariy inquiry is to be made as to the sexual power, which is at 
times increased at the beginning of certain nervous diseases, but gen- 
erally diminishes at a more advanced stage. Anaphrodisia is viewed 
unfavourably by most patients except diabetics. This minor detail 
is not without a certain importance. 

The patient must also be asked whether he has suffered from pre- 
vious affections, particularly gonorrhoea and other venereal diseases, 
and whether he is annoyed by any present trouble, such as spermator- 
rhoea, the frequency of which has been greatly exaggerated. It not 
infrequently happens that patients are worried by some phenomenon 
of an absolutely physiological order. For instance, in continent men 
defecation expels a certain amount of semen through the urethra by 
compression upon the seminal vesicles. 

Examination of the penis reveals the existence of defective con- 
formation, such as epispadias or hypospadias, which represent as 
many stigmata of degeneration. Cicatrices are often found upon the 
organ; it is well to remember, however, that the lesion most impor- 
tant from a semeiological standpoint — viz., the hard chancre — gener- 
ally heals without leaving any trace. The soft chancre is followed 
by a loss of substance which is often quite deep. 

Eruptions, eczema, herpes, syphilitic papules, or mucous patches 
(plaques muqueuses), and sometimes even tumours are found upon 
the penis or scrotum. Another important point to look for is a slight 
mucous or mucopurulent discharge (weeping penis), sequel of a long- 
extinguished gonorrhoea. 

Palpation appreciates the state of the testicle, epididymis, and 
the part neighbouring the deferent canal. In palpating the scrotum 
attention should be directed to ascertain whether or not an inguinal 
hernia exists. The index finger having been introduced into the canal, 
the patient is told to cough; if there is hernia, a shock is perceived. 
Finally, digital examination of the rectum reveals the state of the 
prostate and seminal vesicles. 

In woman, attention is to be first directed to menstruation. The 
points to be noted are : the epoch at which the function was estab-. 
lished; the regularity or otherwise of the periods; the quantity and 



EXAMINATION OF THE SICK 461 

duration of the flow; whether it is attended by pain, or the expulsion 
of clots or false membranes; and whether there are any general dis- 
turbances coincident with menstruation. Investigation is next to be 
made as to leucorrhcea — whether it is intermittent, becoming manifest 
shortly before or after the menses : in that case it is hardly of any 
consequence. In other instances a discharge has appeared and per- 
sisted, which, at first greenish, has gradually become more abundant 
and mucoid; this evidently suggests gonorrhoea. At other times the 
discharge is more tenacious and glairy; it originates from the uterus. 
The odour of the discharges is also of considerable importance. For 
instance, the fetid odour of the reddish discharge of cancer is char- 
acteristic. 

The patient is to be questioned also with regard to the number of 
pregnancies, and whether any abortion or premature birth has oc- 
curred, and, a point of particular interest, whether they occurred with 
or without cause and whether they occurred repeatedly. Eepeated 
abortions otherwise unexplained must be attributed to syphilis. 

Examination of the external organs may reveal various eruptions, 
such as eczema, herpes, and syphilides. A chancre, hidden by some 
fold, may have remained unnoticed by the patient. The presence of 
inguinal adenopathia leads to the diagnosis of, or at least to an ex- 
amination of the vulva for, a chancre. In other instances simply 
tumefaction is observed, oedema of the parts due to some inflamma- 
tory lesion of the vulva or vagina; or a unilateral tumefaction con- 
nected with an affection of Bartholin's gland ; less frequently tumours 
are met with. The state of the urethra requires close attention, since 
gonorrhceal discharges are not so readily recognised in women as 
in men. 

The more deeply seated parts are explored by palpation, which 
recognises cysts of the ovaries, the gravid uterus, or one affected by 
tumours, especially fibromata. It is necessary, however, to make at 
the same time a digital exploration of the rectum and vagina in order 
to well determine the state of the vagina, uterus, Fallopian tubes, and 
ovaries. In the majority of cases this exploration should be completed 
by an examination with the speculum. 

Examination of the Nervous System 

Of all the organs and apparatus of the organism there remains only 
the examination of the nervous system. This last part of clinical re- 
search is particularly long and delicate, requiring especial knowledge. 
We shall therefore be content to indicate the principal rules which 
must guide the physician. 

As has already been mentioned when treating of facies, in certain 



462 INTRODUCTION TO THE STUDY OF MEDICINE 

cases the attention is immediately drawn to the existence of some 
nervous disorder. Paralyses, atrophies, and spasms impart to the 
countenance very peculiar appearances. Intellectual derangements im- 
pose upon it a special expression which can not escape the attention 
of a close observer. 

Motility. — The state of motility is, as a rule, examined first. Ac- 
cording as it is diminished or suppressed, paresis or paralysis is said to 
exist. Paralysis of one limb is called monoplegia ; that of upper and 
lower extremities of the same side, with or without participation of 
the face, is designated as hemiplegia or unilateral paralysis. Hemi- 
plegia is said to be crossed or alternate when the face of one side and 
the limbs of the opposite side are involved. When the two superior or, 
what is a rare occurrence, the two inferior extremities are affected, 
there is paraplegia. Finally, the term partial or limited paralysis is 
employed if loss of movement bears upon a territory of limited extent. 

Paralysis is readily recognised when it is well marked. All motion 
is suppressed in the affected part. When it is raised it falls again 
like an inert mass on being released. In slighter degrees of paralysis 
the affected part is still capable of executing certain motions, but such 
motions are embarrassing and incomplete. For example, a patient 
moves a paralyzed lower limb, but he is incapable of lifting the heel 
from the bed; or he can raise his arm, but is unable to place it over 
his head. It is therefore necessary to push the analysis further and 
not be content to note the paralysis; the degree of the latter should 
be ascertained and the muscles involved in the process determined. 
Paralysis of a limb can generally be recognised without difficulty. It 
will suffice to impart to the limb a certain passive motion and to ask 
the patient to resist it with all his strength, or simply to test the 
strength of his hand grasp. To investigate the state of the muscles 
of the thenar eminence, the following procedure is resorted to : The 
patient is asked to strongly press the thumb against the index finger; 
then a pencil is introduced into the ring thus formed and pushed so 
as to separate the fingers. Under normal conditions the pencil will 
meet with considerable resistance, while in a pathological state the 
fingers will be separated immediately. 

The face must be examined first by a careful inspection. Paralysis, 
by effacing the folds, imparts to the face a marked asymmetry, which 
is further exaggerated by the contraction of the antagonizing muscles 
of the healthy side. The patient will be asked to execute grimaces 
alternately with each side, to blow, to whistle, to wrinkle the forehead, 
and to open and close his eyes. This last investigation is of great im- 
portance, for in cases of facial paralysis the participation or integrity, 
of the orlicularis oculi is one of the best elements of diagnosis as to 



EXAMINATION OF THE SICK 463 

whether the lesion is peripheral or central. The orbicularis is spared 
when facial paralysis is due to a cerebral lesion. It is involved in the 
contrary case, and then closure of the eyes becomes impossible. 

Finally, the patient will be asked to put out his tongue, when the 
tip will be deviated to the affected side, owing to the action of the 
genio-glossus of the healthy side. 

The affected muscles may be relaxed or rigid. In the former case 
paralysis is said to be flabby ; in the latter, that it is attended by con- 
tracture. 

Contracture. — Whether consecutive to paralysis or not, contracture 
is essentially characterized by involuntary and persistent rigidity of 
certain muscles. The muscles thus affected are hard, and their elas- 
ticity appears to be diminished. When an attempt is made to modify 
the situation of the diseased part a peculiar resistance is met with. 
Contracture is frequently accompanied by two phenomena of impor- 
tance to be referred to later on — viz., exaggeration of reflexes and 
epileptoid trepidation. Contracture sets in generally in consequence 
of a traumatism, and disappears during chloroformic sleep or after a 
prolonged application of an Esmarch bandage. 

Contracture may assume a hemiplegic, a paraplegic, or a partial 
form. Although in the majority of instances the antagonizing mus- 
cles are affected, the predominance of certain groups gives rise to a 
peculiar position: thus a type of flexion is mostly observed in the 
superior extremities, while a type of extension generally occurs in the 
lower. The arms stick to the body, the forearm is flexed at a right 
angle, the hand in flexion and pronation, and the fingers forcibly 
closed. In the extension type, the forearm is extended while the fin- 
gers are flexed. In the inferior extremities the several segments are 
in extension, except the toes, which are flexed toward the sole of the 
foot. 

Of partial contractures we shall cite only the glosso-labial hemi- 
spasm of hysterical patients, long confounded with facial paralysis. 

Contracture may be due to hysteria, or be directly or indirectly 
caused by an inflammatory or painful lesion, or connected with some 
affection of the brain, spinal cord, or meninges. All cerebral lesions 
reaching the pyramidal tracts sooner or later give rise to contracture. 
When the latter appears at an early stage it is dependent upon simple 
irritation; when occurring at a later period it is the product of de- 
scending degeneration. Of central diseases it will suffice to mention 
encephalitis, hydrocephalus, tumours, hemorrhages, and softening of 
the brain; of medullary diseases, myelitis, multiple sclerosis, lateral 
amyotrophic sclerosis, and tabes dorsalis spasmodica. Meningitis 
also counts contracture among its symptoms. When this symptom is 



464 INTRODUCTION TO THE STUDY OF MEDICINE 

absent, it may be aroused in the following manner: The patient is 
requested to sit upon the edge of the bed; it is then found that it is 
impossible to extend the knees as completely as when in the lying 
posture : this is known as Kernig's sign. 

The true contractures are not to be confounded with certain mus- 
cular rigidities, designated as pseudo-contractures, which are observed 
in paralysis agitans, pseudo-hypertrophic paralysis, and myopathic 
atrophy. In this case the antagonists are not affected, the reflexes are 
not exaggerated, and chloroform can not dispel the rigidity. 

Gait. — When a patient is affected by a paralysis or a contracture 
which, although involving the lower extremities, still permits the sub- 
ject to walk, a series of disturbances are observed the investigation 
of which is of great semeiological importance. 

In case of flabby hemiplegia, and more particularly in hysteria, the 
leg is dragging: this is the helcopode (cXkcii/, to drag) gait. The sole 
of the foot sweeps the ground. If a certain degree of spasm also exists, 
as occurs in organic hemiplegia, the gait is helicopode (cAikos, circular 
movement) ; the affected limb describes a half circle and comes in 
contact with the ground by the toes. 

With a flabby paraplegia the patient takes short steps with the 
legs widely separated. He alternately drags each of the inferior limbs 
without lifting them from the ground. At each step the pelvis exe- 
cutes alternate movements of inclination and rotation. 

The spasmodic gait of paraplegia with contracture is characterized 
by slow and short steps. The feet are raised with difficulty from the 
ground upon which they rest with the toes alone. At each step they 
turn inward, tending to cross each other; the knees touch and the 
thighs are closely approximated; finally, the trunk inclines alternately 
to the right and to the left, executing real balancing movements 
(cross-legged progression). 

The same manner of gait is observed in paralysis agitans, except 
that in the latter there is an additional feature — viz., an irresistible 
tendency to precipitate the movement — some sort of propulsion which 
has given origin to the saying that the patient appears to be pursuing 
his centre of gravity. By drawing him backward, retropulsion is ob- 
tained. 

In cases of peripheral neuritis steppage is observed. Paralysis of 
the extensors, especially of the triceps and the anterior and external 
muscles of the leg, causes the toes to drop; the patient is obliged to 
raise the leg too high, and the knee being incapable of extension, he 
must strongly flex the thigh upon the pelvis; the toes that remain 
pendent then reach the ground first. This manner of gait, which is 
sometimes described as pseudo-tales, is observed especially in polyneu- 



EXAMINATION OF THE SICK 465 

rites of alcoholic, saturnine, and diabetic origin. It is totally different 
from the gait of true locomotor ataxia. In the latter case there is no 
paralysis; the muscles have preserved their force, but the movements 
are no longer co-ordinated. At each step the leg is thrust too far for- 
ward and outward; the movement exceeds the end and the patient 
brings back the leg, but brings it too far back ; and the leg, being in a 
posture of extension, falls upon the ground with a stamp of the heel. 
When the eyes are closed, this ataxic gait is exaggerated to such a 
degree as to render walking impossible in certain cases. Indeed, it 
is in this manner that the victim sometimes recognises his condition : 
some day on entering a dark room he finds himself incapable of taking 
a step. 

While the diagnosis is easy in advanced cases, it becomes a task of 
considerable difficulty when ataxia is slight. Various procedures are 
then resorted to which reveal the milder manifestations. The patient 
is asked to turn back abruptly or to stand upon one foot; it is then 
noticed that he does so with great difficulty or clumsiness. 

Sclerosis of the posterior columns characterizing ataxia may co- 
exist with sclerosis of the antero-lateral columns (Growers). This is 
combined sclerosis, characterized by spasmodic rigidity of the extremi- 
ties and a peculiar gait designated as tabeto-spasmodic. 

The gait may also be disturbed'by an inco-ordination or rather titu- 
bation recalling that of the drunken man — namely, ebriojis titubation. 
The patient straggles, strays from the line he follows and again returns 
to it, loses his equilibrium and tries to re-establish it by holding the 
arms extended from the body in the manner of a balancing pole. This 
morbid state is observed particularly in cerebellar tumours. It may 
sometimes be associated with spasmodic gait, as occurs in multiple 
sclerosis (cerebello-spasmodic type), and at other times with ataxic 
movements (tabeto-cerebellar type of Friedreich's disease). 

Lastly, there is a strange syndrome — viz., astasia-abasia — in which 
the patient, who has preserved his muscular power and is able to exe- 
cute a great variety of motions, finds himself incapable of remaining 
in the standing posture or of walking in a normal manner; he can 
sometimes walk by assuming strange attitudes. 

The motility of the superior extremities is appreciated in several 
ways. In cases of ataxia motor inco-ordination becomes manifest when 
the victim is asked, with his eyes closed, to touch some part of his body 
with the tip of his finger — the nose, for example. Finally, handwrit- 
ing very readily shows the slightest disorders of motility, which thus 
become considerably magnified. 

Convulsions. — The existence of convulsions is readily recognised, 
not only by the physician but even by those around the patient. This 



466 INTRODUCTION TO THE STUDY OF MEDICINE 

syndrome is characterized by a series of abrupt and involuntary con- 
tractions, which at times last sufficiently long to keep the affected 
part in a determined position for a while (tonic convulsions) ; at other 
times they follow each other in rapid succession, producing a series of 
intermittent movements (clonic convulsions). 

Convulsions may be general or local. 

General clonic convulsions are observed especially in children; they 
occur at the beginning of or during infectious diseases, and are said 
to replace the chills experienced by adults. They sometimes come on 
as the result of some irritation, digestive disorders, intestinal worms, 
teething, foreign bodies, or simple emotion. Although regarded by 
many clinicians as commonplace manifestations, they are, even in 
children, really dependent upon nervous heredity. 

The influence of heredity and innateness, and of antecedent causes 
that have acted upon the nervous system, likewise explains the appear- 
ance of convulsive phenomena in the adult. Convulsions may be mani- 
fested in the course of infections and intoxications, such as uraemia 
and puerperal eclampsia, but the nervous localization of the process 
is rather connected with the predisposition. The fact should not, how- 
ever, be exaggerated. Whatever may have been the previous state of 
the nervous system, convulsions are inevitable in certain cases. This is 
what takes place in certain intoxications or infections which, like 
strychnine or tetanus, affect the medullary centres and there give rise 
to an extraordinary hyperexcitability. 

Epilepsy, hysteria, and medullary lesions are among the number 
of nervous diseases which most frequently give rise to convulsions. It 
is, however, in cases of local or partial epilepsy that this syndrome 
becomes most interesting. 

By partial, symptomatic, or Jacksonian epilepsy is meant a syn- 
drome characterized by convulsive movements affecting a part or one 
half of the body. Convulsions of the hemiplegic type, which are 
analogous to those of epilepsy, involve progressively the two limbs 
and the face on one side, but they are not accompanied by loss of con- 
sciousness, at least at the beginning of the attack. The patient, there- 
fore, witnesses his own paroxysm, and, unlike the epileptic, retains the 
memory of it. 

Jacksonian epilepsy indicates a lesion in the hemisphere of the 
opposite side and serves diagnosis at least as a guide to localization. 
In fact, it will suffice to remember that convulsions begin with the 
part corresponding to the psycho-motor zone occupied by the lesion. 
Hence, if convulsions first appear in the face, the lesion must be seated 
in the corresponding centre — namely, in the lower part of the parietal 
and ascending frontal convolutions; if in the hand, then the middle 



EXAMINATION OF THE SICK 467 

part of the same convolutions is altered; if in the foot, the lesion 
is located in the upper part of the ascending convolutions as well as in 
the corresponding part of the paracentral lobe. 

Tics, Cramps, Trembling, Chorea. — Certain involuntary movements, 
not very different from convulsions, may be considered here. 

Tics are characterized by the abrupt, involuntary, and habitual 
contractions of one or several muscles describing a co-ordinated move- 
ment. They are commonly observed in the muscles of the face. 

In some cases tics constitute almost a morbid entity, the so-called 
disease of tics, the clinical picture of which is completed by what is 
known as coprolalia and echolalia. Echokinesia is also observed, 
which permits identification of the disease of tics with the jumpers' 
disease of Maine and Canada (Beard), latah of Java (O'Brien), and 
myriachit of Siberia (Hammond). 

In general, tics are readily recognised. Paramyoclonus multiplex 
is distinguished by the character of the jerks, which do not, as a rule, 
involve the face and rarely outline a co-ordinated movement. Tics are 
not to be confounded either with occupation cramps, which are mani- 
fested on the occasion of certain movement, such as the cramps of 
writers, telegraphers, and pianists. 

Trembling or tremors is a motor disturbance of great semeiological 
importance. It consists of a series of short oscillations which do not 
interfere with voluntary movements except by simply diminishing their 
precision. 

Three varieties of trembling motions have been distinguished : ( 1 ) 
those with rapid rhythm, having from 8 to 12 oscillations per second; 
(2) trembling of medium rhythm, having from 5 J to 7 J oscillations; 
and (3) slow trembling, not presenting more than 4 or 5^ per second. 

Tremblings are also divisible into two types according as they are 
more marked at rest, disappear during voluntary movements (paralysis 
agitans), or begin with the movements and become more and more 
pronounced as the end is approached (multiple sclerosis). It is pos- 
sible also to speak of general, or at least extensive, trembling and of 
one limited to a limb, assuming at times the hemiplegic type. 

Chorea is an affection observed mostly in children, having a dura- 
tion of from two to four months. This is Sydenham's chorea. When 
it appears in the aged it is incurable, and is known as Huntington's 
chorea. 

Chorea should not be confounded with certain morbid states which 
from their causation, evolution, and even symptoms are quite distinct 
from it. Such, for example, are the electric chorea of Dubini, the 
electric chorea of Bergeron, the fibrillary chorea of Morvan, Salaam's 
tic, and more particularly hysterical chorea, the rhythmical, co-ordi- 



468 INTRODUCTION TO THE STUDY OF MEDICINE 

nated jerks of which often represent the designed motions of the pa- 
tient's occupation or trade, but are quite different from the purpose- 
less and illogical movements of true chorea. 

Hemichorea is characterized by truly choreic movements, except that 
these are limited to one half of the body and appear in the course of, 
or consecutively to, hemiplegia of cerebral origin. Moreover, the limbs 
attacked with hemiplegia are at times agitated by involuntary move- 
ments analogous to those of chorea, but are accomplished with extreme 
slowness. This is hemiathetosis, first described by Hammond, which is 
dependent upon cerebral lesions. When both sides of the body are 
involved the morbid state is generally congenital and often accom- 
panied by intellectual defects, idiocy, imbecility, or epileptiform at- 
tacks. They are attributed to diffuse lesions of the brain with involve- 
ment of the posterior segment of the internal capsule. 

Reflexes. — The investigation of motor disturbances must be com- 
pleted by testing the state of the reflexes. 

The tendon reflexes are first examined. Such is the name given to 
contraction suddenly produced in a muscle when its tendon of inser- 
tion is struck. The patellar tendon is the one commonly chosen for 
this research. The patient sits upon a table or upon the edge of his 
bed, with the legs hanging. Or he may be seated upon a chair and 
requested to cross one leg upon the other; or, if he is reclining, the 
lower part of his thigh is raised and supported by the examiner's left 
arm. The patellar tendon is then percussed either with the tips of 
the fingers or with the ulnar edge of the hand. Under normal con- 
ditions, a sudden contraction of the quadriceps femoris is obtained, 
and the foot is thrown forward. Under pathological conditions, the 
reflex may become increased; in certain cases it is so exaggerated 
that the effect, exceeding the region excited, is expressed by an abrupt 
movement of both lower extremities. In other instances, it is dimin- 
ished or even abolished. In the latter case it is well to begin the 
exploration by asking the patient to strongly press the hands one 
against the other; in this manner all involuntary contraction in the 
lower limbs is suppressed and the reflex sometimes reappears. 

Increase in the patellar reflex is observed in a great number of 
affections, particularly in all those in which contracture exists. When 
it appears in the course of flabby hemiplegia, it indicates that con- 
tracture is imminent. 

Among those diseases which give rise to increased patellar reflex 
may be cited multiple sclerosis, transverse myelitis, sclerosis of the 
pyramidal column, lateral amyotrophic sclerosis, certain medullary 
compressions; intoxications, such as hydrargyrism ; and neuroses, as 
neurasthenia. As to suppression of the reflex, it is met with in loco- 



EXAMINATION OF THE SICK 469 

motor ataxia (WestphaPs sign), pseudo-tabes from peripheral neu- 
rites, infantile paralysis, acute spinal paralysis, and certain circum- 
scribed compressions of the cord. 

When the patellar reflex is very markedly exaggerated another 
morbid phenomenon designated as epileptoid trepidation may be called 
forth. The patient being on his back, the ends of the toes are grasped 
and abruptly extended; rapid contractions are immediately produced 
in the triceps, which are expressed by a series of movements of ex- 
tension and flexion in the foot. In some instances the same experi- 
ment elicits a spasmodic contraction that maintains the foot for 
a few moments fixed in the position given to it. 

The tendon reflexes may also be tried in other parts of the body — 
for example, in the wrist or in the lower jaw — but it is of far less 
importance than in the knee. 

More interesting are the superficial reflexes, and among these the 
cutaneous reflexes. In this connection are investigated the effects 
produced by tickling the sole of the foot, by exciting the muscles of 
the abdomen or of the anal region, and the " cremaster reflex," which 
is elicited by excitation of the inside of the thigh and is attended 
by retraction of the testicle. This reflex is especially intense in 
children. 

The reflexes that may be produced in certain mucous membranes 
should next be sought for. The nauseous reflex, the nature of which 
is sufficiently obvious from its name, is elicited by touching the palate 
or the fauces; it is absent in various nervous diseases, particularly 
in hysteria. Excitation of the conjunctiva arouses a reflex contrac- 
tion of the eyelids. Excitation of the glans penis produces contrac- 
tion of the urethral bulb, known as the bulbo-cavernous reflex, etc. 

Contractions appearing at times in muscles when percussed should 
not be mistaken for reflexes. This phenomenon, designated as idio- 
muscular contraction or myoideme, is obtained especially in the pectoral 
muscles and the biceps. By slightly tapping over the former a series 
of fibrillary contractions are caused, which appear as a cord beneath 
the skin. As to the biceps, the muscle is taken hold of between two 
fingers, forcibly raised and dropped, when a transverse ring becomes 
manifest. This phenomenon is frequently observed in wasting dis- 
eases and in cases of rapid emaciation. It is very well marked in 
tuberculosis and often more accentuated upon the more profoundly 
affected side. 

Sensibility. — The sensory disturbances may be divided into two 
groups : those of which the patient is conscious and for which he 
generally seeks medical advice, and those which the physician must 
carefully look for. 



470 INTRODUCTION TO THE STUDY OF MEDICINE 

The former are subjective symptoms consisting of pains or anoma- 
lous sensations. 

Pains possess a high degree of importance in semeiology. From 
the beginning of the interrogation they lead the physician to the path 
of diagnosis, drawing his attention to a region or organ. In fact, 
it is of greater consequence to determine the seat than the character 
of sensations experienced. Of course, in certain cases the informa- 
tion given by the patient as to the sensory phenomena from which he 
suffers is of interest: the sharp, pulsatile, shooting, fulgurating, 
drawing character of the pains sometimes guides the physician. In 
general, however, it is better to lay stress upon the location. After 
the region is decided, it is necessary to determine whether the pain is 
superficial or deep seated, diffused or confined to a limited territory, in 
an organ or in some important part of an organ, occupying the surface 
of a muscle or following the course of a nerve. When these primary 
results are obtained, then the region is carefully palpated to decide 
whether pressure increases or diminishes the pain, whether some 
spots are more painful than others, and whether voluntary or passive 
movements cause exacerbation. Likewise, it is well to determine 
whether certain external conditions modify the sensations complained 
of. For example, one pain may be relieved by cold, another by heat, 
and a third may become intensified during the night. The nocturnal 
exacerbation of cephalalgia points decidedly to a syphilitic origin. 

Furthermore, it should be borne in mind that the site of pain is 
not necessarily connected with the seat of the lesion. When a nerve 
is compressed the phenomena of pain are not pronounced at its ter- 
minations. The same is true of diseases of the spinal cord. The 
gastric, the fulgurating, and the girdle pains of locomotor ataxia are 
peripheral manifestations of the central lesion. 

Finally, when pains express some general derangement, their loca- 
tion is no longer of any importance. Headache, of which patients so 
often complain in the course of the most varied morbid states, should 
not lead us to look for or admit an intracranial lesion. Eachialgia, 
which is so frequent at the beginning of certain eruptive fevers — in 
smallpox and more rarely in measles — indicates at most a certain 
congestion in the spinal cord, without being of itself of any value 
with reference to localization. 

Then the patient must be questioned whether he has experienced 
any anomalous sensations — formication or subjective impressions of 
cold or heat. Under a great variety of circumstances, and notably in 
neurasthenia, the patients complain of flashes of heat; in paralysis 
agitans they are always too warm. Lastly, a painful or troublesome 
sensation may be felt along a limb or a nerve and precede a nervous 



EXAMINATION OF THE SICK 471 

attack, particularly an epileptic paroxysm: the phenomenon is desig- 
nated as an aura. 

After having interrogated the patient, the sensory disturbances 
are to be sought for, and to this end the . thermal and the tactile 
sensibility, as well as the sensibility to pain, must successively be 
examined. 

Tactile sensibility is tested by the touch of a finger, or a pointed 
metallic object, or still better with the sharp edge of a sheet of paper. 
Care should be taken to avoid pressure in order not to call into play 
the deeper sensibility. 

In investigating sensibility, we must determine whether it is pre- 
served, diminished, or increased; whether the sensation is perceived 
at the excited point and corresponds to the excitation and is produced 
in normal time. 

Sensibility may be absent all over the integument, upon the mu- 
cous membranes as well as upon the skin. This condition is hardly 
ever realized in any morbid state other than hysteria. In the major- 
ity of cases anaesthesia is distributed in the form of disseminated 
plates, at times associated with plates of hyperesthesia, or it may 
affect a limb, one half of the body, or the inferior extremities. In 
dealing with such complex cases it is well to record the various dis- 
turbances observed upon a schematic design representing the gen- 
eral appearance of the body. 

When the patient is still capable of feeling, it must be decided 
whether sensation is referred by him to the point excited. To this 
effect the patient is directed to close his eyes, and is then asked to tell 
exactly in what region stimulus is applied. It is next determined 
whether the sensation is precise. The patient at times perceives two 
contacts, while there is only one; and more frequently he declares 
there is but one, while there are two. In order to appreciate this 
phenomenon, a small apparatus called asthesiometer should be used. 
This is much like a pair of compasses with two points, one fixed and 
the other movable over a graduated quadrant. By means of this in- 
strument it can readily be determined at what distance the two excita- 
tions fuse into a single sensation. 

It should also be decided whether perceptions are as rapid as 
in a normal state. It is to be remembered that the time elapsing 
is proportionately longer as the point explored is farther removed 
from the centres, perception being most delayed in the case of the 
end of the foot. In certain instances delay is long enough to 
be readily appreciated. When it is less marked registering appa- 
ratus must be resorted to, which can not be made use of in ordinary 

clinics. 

31 



472 INTRODUCTION TO THE STUDY OF MEDICINE 

Diminution or increase in the sense of touch may coexist with 
analogous modifications in thermal sensibility. The most interest- 
ing cases, however, are those in which the two orders of perception 
are differently modified. This is what occurs in syringomyelitis : tac- 
tile sensibility is normal while thermal sensibility is suppressed, so 
that the patient constantly burns himself without minding it. To 
appreciate thermal sensibility, glass tubes containing hot or cold 
water are applied to the skin. When more precise information is 
desired, a thermometer is dipped in the tube, and very exact results 
are thus secured in employing liquids of gradually increasing tem- 
perature. 

Sensibility to pain is appreciated by pinching or pricking the skin, 
or by employing an interrupted electrical current. It is thus deter- 
mined that analgesia and anaesthesia do not necessarily coincide. 
Analgesia may even coexist with spontaneous pains, as occurs in 
locomotor ataxia, in compressions of the cord, and in certain forms of 
neuritis. 

Hyperalgesia, or increased sensibility to pain, may be superficial 
or profound. In the latter case forcible pressure is required to pro- 
duce pain in subjacent organs. It is not rare to find in hysterical 
individuals some deep-seated hyperalgetic zones, the excitation of 
which gives rise to a convulsive paroxysm, or, on the contrary, arrests 
one just beginning. Of these so-called hysterogenic zones the most 
important ones are seated at the vertex, in the dorsal region of the 
spine, at the nipple, under the mammary gland, in the ovarian region, 
in the testicles, and in the patella. 

All muscular action excites subjective sensations informing us of 
the movement accomplished — i. e., of the force displayed and the 
situation of our muscles. This muscular sense is suppressed in certain 
nervous diseases. The patient is unaware of the position occupied 
by his limbs. If, his eyes being closed, we move his lower extremities, 
he is unable to tell in what position they are placed. This phenome- 
non, which is observed in a great number of spinal or cerebral diseases, 
is particularly frequent in locomotor ataxia. The patient often loses 
the sense of power displayed; this is a commonplace disorder and 
occurs in all forms of paralysis, and therefore is without value. More 
interesting is the loss of the sense of effort which occurs in medullary 
paralyses involving the glottis. This phenomenon can readily be 
understood in view of the fact that the integrity of the glottis is 
indispensable for the production of effort. 

Obgans of Sense. — After the examination of general sensibility, 
the state of the special sense — that is, of the organs of sensibility — 
must be investigated. 



EXAMINATION OF THE SICK 473 

It is usual to first take up the sense of vision, which is the most 
important from a semeiological standpoint and the most difficult of 
exploration. 

Leaving aside what belongs to the study of ophthalmology, we 
shall consider only those explorations which every physician must 
make. 

As always, the first step is to ask the patient questions with re- 
gard to phenomena of pain. These are sometimes sensations of for- 
eign bodies, at other times photophobia and ocular and often peri- 
orbital pains. 

The visual apparatus is examined to determine successively the 
state of the eyelids, conjunctivae, cornea, and iris; the state of the 
external and internal musculature of the eye; the sensibility of the 
external parts; the state of the secretions; the visual acuity and 
the field of vision. 

The eyelids are often the seat of lesions which are without grav- 
ity — i. e., blepharitis, and particularly ciliary blepharitis, eczema, hor- 
deolum, etc. In the conjunctivae the state of vascularization is to be 
examined, and in certain instances phlyctenule and vegetations must 
be sought for. Then the cornea should be examined, which may be 
the seat of ulcers or cicatrices, the presence of which is of great diag- 
nostic value, and, finally, the iris, which is at times deformed or 
affected with pigmentary lesions. 

Then passing to the examination of the musculature, care should 
be taken to have the patient well facing the light. The movements 
of the eyelids are first taken into consideration. As already stated, 
the condition of the orbicularis is of considerable semeiological impor- 
tance. While this muscle is affected in case of peripheral facial paral- 
ysis, it is spared in central paralyses. In other instances a spasmodic 
semiclosure is observed. This is blepharospasm, which, when not 
referable to a reflex caused by photophobia or pain (foreign body, 
conjunctivitis, iritis), is pathognomonic of hysteria. 

Finally, ptosis or drooping of the upper eyelid is connected with a 
limited or extensive paralysis of the third pair. It often coexists 
with paralyses of the oculo-motors and dilatation of the pupils. 

When the ocular globe or the eyeball protrudes between the eye- 
lids more than is natural, exophthalmia is said to exist. If this symp- 
tom is unilateral, it immediately suggests a tumour of the orbit, or an 
abscess pushing the eyeball forward. Bilateral exophthalmia, which 
is especially pronounced in case of exophthalmic goitre, imparts to 
the patient an altogether peculiar appearance of astonishment. 

Examination of the ocular movements may demonstrate that both 
eyes do not look in the same axis. This phenomenon is due either 



474 INTRODUCTION TO THE STUDY OF MEDICINE 

to a defective congenital conformation or to a local or general paral- 
ysis of one or both oculo-motors. In investigating ocular paralyses the 
patient is instructed te follow with his eyes an object which is being 
displaced successively to the right, to the left, upward and downward. 
Knowing the physiological role of the various muscles, it is easily deter- 
mined in which muscle or set of muscles activity has ceased. It must 
next be decided which nerve is affected, and whether in its entirety 
or in some of its branches. Then, taking into account the accom- 
panying manifestations, it will be possible to recognise the seat and 
cause of the lesion of which the paralysis is but a symptom. 

There is a particular syndrome — i. e., external ophthalmoplegia — in 
which all the external muscles of the eye are paralyzed. It is gener- 
ally dependent upon locomotor ataxia, cerebral syphilis, exophthalmic 
goitre, or bulbar paralysis. 

Although ocular paralyses are unilateral in most cases, they may 
also be double. In the latter case quite important disorders result. 
The paralysis causes dissimilar, nonconjugated ocular deviations. 
This event, of rare occurrence, is observed especially in syphilis, 
ataxia, and diabetes. At other times deviation is in the same direc- 
tion, both eyes looking to the same side, right or left. This conjugate 
deviation of the eyes is met with in upper medullary paralyses; it 
often makes its appearance, although in a transitory manner, at the 
beginning of multiple sclerosis. Finally, it may coexist with a similar 
deviation of the entire head, and then it is called conjugate deviation 
of the head and eyes, which is of very frequent occurrence in the 
course of encephalic lesions. When it coincides with hemiplegia, it 
obeys the following two laws, which serve to determine cerebral local- 
izations : 

1. When the lesion affects the hemispheres, the patient turns away 
from his paralyzed limbs, or, as is sometimes said, looks to his lesion. 
If an excitation takes place, the attitude changes : instead of looking 
to his lesion, he looks to his convulsed extremities. 

2. When the lesion involves the mesocephalus, the law is reversed : 
The patient looks at his paralyzed limbs, and turns away from them 
when he becomes excited. A disorder more difficult of comprehen- 
sion is what is described as asthenopia. Contraction of the two inter- 
nal recti muscles becomes insufficient for near sight — say, for read- 
ing. Then a sense of fatigue, a visual disturbance is produced. When 
this syndrome is not accounted for by any lesion of the eyeball or its 
muscles, it is due to a nervous disease, exophthalmic goitre, hysteria, 
and, above all, neurasthenia. 

Of the disturbances of a spasmodic character, nystagmus deserves 
mention. It is characterized by oscillatory movements of the eyeballs, 



EXAMINATION OF THE SICK 475 

usually horizontal (horizontal n.), more rarely vertical, oblique, or 
even rotary. It is at times congenital. It may occur in miners (n. of 
occupation) ; but it is especially frequent in multiple sclerosis, in 
Friedreich's disease, cerebral tumours, and encephalitis. 

Then the examination of the internal muscles of the visual appa- 
ratus — viz., of the iris — is taken up. The points to be noted are 
whether the pupils are more or less dilated than normally; whether 
they are regular, perfectly circular, and equal. Their contractility is 
also tested under two different conditions : in the light and at dis- 
tances. In order to appreciate the influence of light, the eyes are 
closed for a few minutes and then suddenly opened, care being taken 
to have the patient facing the light or to place before his eyes a 
lighted match. The pupil, which had dilated during the palpebral 
closure, immediately contracts. Accommodation is examined by di- 
recting the patient to look alternately at near and far objects, when 
it is noticed that the pupil dilates in the former case and contracts 
in the latter. This examination is of very great semeiological impor- 
tance. Persistence of accommodation to distance with suppression of 
accommodation to light is a sign which is hardly ever met with in 
pathological conditions other than ataxia and general paralyses. It 
is called the Argyll-Robertson sign. 

Suppression of the movements of the pupil is observed in lesions 
of the ciliary nerves or their nuclei of origin, and in inferior radicular 
brachial paralysis ; it then coexists with miosis. 

By internal ophthalmoplegia is designated paralysis of the internal 
musculature of the eye, with mydriasis as its dominant symptom. 
This disorder at times coincides with external ophthalmoplegia, thus 
constituting total ophthalmoplegia. These various manifestations 
are observed in tabes dorsalis, when they are generally unilateral, and 
in the atrophy of the nuclei of the cranial pairs, in which they are 
bilateral and progressive. 

Tactile sensibility of the external parts is lost in certain central 
lesions and in hysteria. The conjunctivae may then be touched with- 
out causing pain or palpebral contraction. This disturbance has 
already been referred to in connection with sensitivo-sensorial hemi- 
anaesthesias. 

Conjunctival hyperesthesia is observed in certain neuropathic sub- 
jects, and in cases of inflammatory lesions of the profound or super- 
ficial parts of the eye; when it is intense, it produces blepharo- 
spasm. 

We shall not dwell upon modifications in the secretions, the study 
of which belongs to the domain of pure ophthalmology. It will suf- 
fice to bear in mind that, in certain cases the lachrymal secretion 



476 INTRODUCTION TO THE STUDY OF MEDICINE 

flows over the cheeks, as occurs when the excretory canal is obstructed, 
and in cases of peripheral facial paralysis (paralysis of Horner's 
muscles). The quantitative modifications of the secretion have not 
yet been much investigated. All that has been noted in connection 
with this subject is the loss of the faculty of shedding tears in certain 
neurasthenics, and the facility with which tears are shed by hysterical 
individuals. The crisis of tears following a convulsive attack may 
be of some importance to differentiate an hysterical from an epileptic 
paroxysm. 

The secretions of the palpebral glands are exaggerated in inflam- 
mations of the eyelids, of which they cause the agglutination. Exu- 
dates may also be produced, either pseudo-membranous, and then 
generally diphtheritic, or purulent. We have repeatedly referred to 
purulent ophthalmia, which in the majority of cases is connected with 
the presence of the gonococcus. 

Examination of the ocular apparatus is terminated by an inquiry 
into the state of vision. 

The points to be looked into are as follows : Ask the patient 
whether he suffers from any disturbance; then examine as to his 
vision with both eyes and with one eye, and then determine succes- 
sively whether he sees the object, whether he sees it in the different 
situations through which it is carried, and in its real form and 
contour. 

The troubles experienced by the patient are of several orders. 
At times he notices that he does see the objects as clearly as he used 
to, or that his sight is becoming short. At other times he com- 
plains of double vision (diplopia), or of no longer exactly recognising 
forms and colours. In yet other instances, false images disturb his 
vision; he experiences subjective sensations which he knows well to 
be unreal. In this last case there may be nothing more in the field 
of vision than some fixed or moving black spots (mouches volantes). 
At other times the illusion is more intense and is expressed by lumi- 
nous sensations designated as sparkling scotoma. The patient sees 
before his eyes an irregularly outlined shining spot, moving slowly, and 
often surrounded by sparks. This phenomenon, which occurs in 
paroxysms, is one of the symptoms of ophthalmic migraine, and is fre- 
quently met with in the beginning of grave nervous diseases, such as 
general paralysis. It is a subjective event, which must carefully be 
distinguished from analogous sensations connected with optic lesions 
and alterations of the eyeball. In the former case ophthalmoscopic 
examination demonstrates the presence of lesions at the fundus of the 
eye; in the latter, pressure upon the eyeball produces deformation 
of the scotoma. 



EXAMINATION OF THE SICK 477 

In addition to what a patient can frequently tell with regard 
to his visual modifications, the physician must, as a rule, look care- 
fully for disturbances. 

Diminished visual acuity, or amblyopia, is readily recognised. It 
remains, however, to determine its variety; whether it is due simply 
to a weakening of perceptions, or is referable to scotomata — i. e., 
blind spots in the field of vision. 

For examining the scotomata the following process is resorted to : 
The patient is instructed to alternately close each eye, and then to 
gaze with the open eye at some point, while an object is displaced; 
the patient must tell at what moment he ceases to see the moving 
object. 

Scotoma is central or peripheral. If it is peripheral, the moving 
object becomes invisible as soon as it is a little removed from the 
point stared at. The field of vision is then said to be narrowed. 

A central or peripheral scotoma associated with loss of pupillary 
reflex is a symptom of optic neuritis or tabes dorsalis. The two vari- 
eties can be distinguished by means of ophthalmoscopic examination. 
An amblyopia of the same order is also observed in intoxications by 
alcohol or tobacco. In this case, however, the scotoma is central and 
regular. Analogous disturbances are produced under the influence of 
diabetes and uraemia. Narrowing of the field of vision with preserva- 
tion of the pupillary reflex is one of the sure signs of hysteria. 

The field of vision may become suppressed in one half of the eye, 
a morbid state known as hemiopia or hemianopsia. It may be uni- 
lateral or bilateral, occupying the external or the internal half of the 
visual field — in other words, the temporal or the nasal side. 

A monocular hemiopia or a heteronymous bilateral hemiopia indi- 
cate a lesion of the optic nerve. Heteronymous bilateral hemiopia, 
which is temporal in most cases, generally depends upon a tumour of 
the pituitary gland, and is an important symptom in acromegalia. 

Homonymous hemiopias are divided into two groups, according as 
the pupillary reflex is lost or intact. In the former case there is 
lesion of the optic nerve ; in the latter, there is cortical or subcortical 
cerebral lesion. The variety most frequently encountered is a right 
lateral hemiopia, coinciding in general with word blindness, and is 
connected with a lesion of the curved gyrus. In this instance the 
patient is blind on the right half of the field of vision: he is there- 
fore affected with right temporal and left nasal hemiopia. 

Contrary to what one might believe, diplopia is a manifestation 
which must often be sought for. A patient who is affected with it as 
a result of ocular paralysis no longer perceives it after the lapse 
of some time, for the reason that, through a special position of the 



478 INTRODUCTION TO THE STUDY OF MEDICINE 

head, he succeeds in bringing both of his eyes to the same axis; or 
else he unconsciously suppresses the vision of one eye. It is possible 
to cause the phenomenon to reappear by asking the patient to fix his 
view upon an object which is then moved. The paralyzed eye will 
be unable to follow it in certain directions, and the image, being im- 
pressed upon nonsymmetrical parts of the retina, will appear double. 

Finally, if one eye of the patient be closed, and an object be pre- 
sented before the other, and be carried near and far, it will sometimes 
happen that the individual sees at a certain distance several objects 
instead of one, or the object will suddenly appear to be smaller or 
larger. These various phenomena, designated as diplopia, monocular 
polyopia, micropia, and megalopia, are observed only in hysteria. 

Chrornatopsia is tested by presenting to the patient papers or tex- 
tures of various colours and asking him to name the tints. It is 
preferable to give him skeins of wool of assorted colours and ask 
him to separate and classify them. He is then seen to confound the 
most sharply distinct colours. 

Two orders of disturbances are distinguished in the perception of 
colours. There is sometimes achromatopsia — namely, absence of cer- 
tain perceptions — and sometimes dyscliromatopsia — i. e., confusion of 
colours. This latter variety is particularly frequent in hysteria ; when 
it coexists with narrowed field of vision, it is pathognomonic of the 
neurosis. 

Achromatopsia is met with in hysteria, tabes dorsalis, and intoxi- 
cations by alcohol and tobacco. The disappearance of the different 
colours does not, however, take place in the same order. In hysteria, 
achromatopsia begins with violet, extends to yellow, green, and, much 
later, to red. In the other cases the perception of red is lost first. 
In tabes the perception of yellow persists very long; it is still present 
at an advanced stage when the patient has become almost blind. 

Examination of the auditoey appaeattjs is generally made in a 
summary manner in current clinics. 

The patient is questioned as to the sensations he experiences. The 
latter are divided into three classes. In some cases there is diminu- 
tion of auditory acuity; in others there is increased auditory sensi- 
bility, so that somewhat strong noises give rise to painful sensations ; 
finally, the patient may complain of subjective sensations — tingling in 
the ears, anomalous phenomena, murmurs, whistling, etc. 

Exploration is at first confined to a search for lesions or some dis- 
charge in the external parts. Then, having the patient face the light, 
and strongly drawing on the pavilion of the ear, the external meatus 
is looked into to discover certain alterations, and especially the pres- . 
ence of accumulated cerumen. 



EXAMINATION OF THE SICK 479 

Investigation of auditory acuity is readily made by means of a 
watch, which is at first placed at a certain distance and is then grad- 
ually brought nearer the ear. It is well to supplement the exploration 
by applying the watch or, still better, a tuning fork to the vertex of 
the head. If, under these conditions, the affected ear should hear 
the sounds as well as the healthy ear, it is concluded that the cen- 
tral parts are intact; if not, then a labyrinthian lesion is to be 
admitted. 

The tympanum also should be examined by auscultating the ear 
of the patient, either by applying one's own ear to that of the patient 
or by employing a stethoscope or Toynbee's tube. The patient having 
closed his nose and mouth, the physician perceives a slight crackling 
murmur when the patient swallows his saliva. 

In the majority of cases these various modes of exploration must 
be supplemented by more exact procedures. Examination of the ear 
necessitates the use of some special instruments. There are two 
which every physician should know how to make use of: the aural 
speculum, which permits the study of the external auditory canal and 
the tympanum; and the sound of Itard, which shows the condition 
of the middle ear by permitting catheterism of the Eustachian tube. 

Taste and smell become diminished or suppressed in a great 
number of infectious or toxic diseases. The catarrhal state of the 
nasal fossae, dryness of the mouth, and coated condition of the tongue 
interfere with the normal play of these various parts. In other cases 
subjective disorders of a truly hallucinatory character are observed, 
along with analogous disturbances of the eye and vision. The patient 
complains of perception of generally disagreeable odours, or of a bad 
taste in the mouth, and, quite often, these subjective sensations give 
rise to a particular delirium: they lead the patient to the belief that 
he is the object of attempts at poisoning. 

In exploring these two senses care should be taken to distinguish 
their special from their general sensibility. 

Taste is tested by placing upon the tongue sweet or bitter sub- 
stances, such as sugar or quinine. 

Olfaction is investigated by placing under the nose aromatic sub- 
stances, such as essence of peppermint, Cologne water, asafcetida, or 
musk. In this connection the use of irritating substances should 
be avoided, such as acetic acid and ammonia, which, apart from 
their odorous properties, possess the power of arousing general sen- 
sibility. Their nonperception indicates paralysis of the trigeminal 
nerve. 

The various modes of sensibility may be suppressed in one half 
of the body. There is then a syndrome of great importance — viz., 



480 INTRODUCTION TO THE STUDY OF MEDICINE 

sensitivo-sensorial hemiancesthesia. It consists in the suppression of 
cutaneous and profound sensibility, of the muscular sense, of the 
senses of taste, smell, and hearing, along with narrowed field of vision 
and diminished pharyngeal reflex, while the tendon and skin reflexes, 
the pupillary reflex, and the response to painful impressions are nor- 
mal. This syndrome is met with under two pathological conditions — 
viz., hysteria and lesions of the internal capsule in the sensory cross- 
way (carrefour sensitif). 

ClBCULATOEY, SECEETOKY, AND KeSPIEATOBY DlSTUBBANCES. — 

The frequency of vasomotor derangements has repeatedly been 
alluded to, particularly in connection with the integument. 

The disturbance sometimes consists in vaso-constriction, which is 
especially marked in the extremities, as evidenced by the " dead 
finger," and, in a more advanced degree, syncope of the limbs, with 
a possible termination in small points of sphacelus. Or there may be 
venous congestion, or cyanosis, as occurs in asphyxia of the extrem- 
ities. Finally, a congestion through active vaso-dilatation is often 
produced in the course of the most varied nervous diseases. Sudden 
redness of the cheeks in the beginning of meningitis, and the white 
line which may be produced with the nail upon the skin of the abdo- 
men, are well-known phenomenon. Trousseau used to attach great 
importance to this meningeal streak {rate meningee). At the present 
day it is known that this phenomenon simply indicates vasomotor 
paralysis, and, furthermore, that in order to be worthy of considera- 
tion it must fulfil the following two conditions : appear slowly and 
disappear slowly. 

A vasomotor disturbance may terminate in fluxions, which occur 
most frequently in the cervical region and mammary glands. In hys- 
teria this gland is sometimes so voluminous and painful that it has 
more than once been considered as affected with cancer and treated 
by operation, which was at least useless. 

In a more advanced stage vasomotor disorders end in a vascular 
rupture. The hemorrhage taking place in the skin or on the mucous 
membranes is expressed by bloody tears, epistaxis, hemoptysis, or 
hematuria. These hemorrhages are sometimes caused by organic 
lesions, but are due to hysteria in most cases. 

It is superfluous to enlarge upon secretory disturbances, which have 
already been referred to incidentally. 

Sialorrhcea is not an event of rare occurrence; a simple hemi- 
crania or neuralgia suffices to produce it. It is at times the premoni- 
tory phenomenon of an epileptic attack. 

Diaphoresis, suppressed in neuritis, is often exaggerated in cases, 
of neuralgia or lesions of the medulla. 



EXAMINATION OF THE SICK 481 

Diuresis may present similar variations. As already stated, the 
urine increases when excitation is slight, and decreases when it is in- 
tense. 

Finally, even the visceral secretions may undergo marked changes. 
Crises of hypersecretion of hydrochloric acid in the stomach, gastror- 
rhcea, and enterorrhcea are observed in diseases of the spinal cord, 
such as tabes dorsalis, and in neuroses, such as hysteria. They are 
particularly frequent in neurasthenia, although discussion is still open 
as to whether the digestive symptoms depend upon the nervous affec- 
tion, or the latter is a product of the bad state of the gastrointestinal 
functions. The latter hypothesis is more plausible. The digestive 
derangements render the neurosis manifest in predisposed individuals. 

It is also important to remember that lesions or disturbances of 
the nervous system often influence the respiratory function. Lesions 
of the medulla oblongata may give rise to dyspnoea. Weir Mitchell 
has described an hysterical tachypncea characterized by an extraordi- 
nary acceleration of the respiratory movements, amounting in some 
cases to from 40 to 100 or even 120 per minute, without the patient 
appearing to make any effort. 

Tkophic Distukbances. — Of all the nutritional disorders occur- 
ring in nervous diseases, those bearing upon the muscular system are 
decidedly the most important. 

Muscular atrophy is readily recognised by modifications in the 
appearances of the affected parts. The eminences are effaced, the 
bones become apparent, the regions are deformed, either as a result of 
atrophy or by the retraction of the antagonists, whose action is no 
longer counterbalanced. The result is modifications which are par- 
ticularly notable in the hands (preacher's hand, monkey hand, skele- 
ton hand), spinal deviations or curvatures of a compensating nature, 
destined to re-establish the equilibrium. It must be noted that atro- 
phy of the muscles is sometimes masked by adipose tissue; the latter 
may be seated in the muscle itself and impart to it a volume equal or 
even superior to the normal: pseudo-hypertrophy is then said to 
exist. When fat is subcutaneous, it disguises the lesion, but it is 
readily proved by making a fold upon it. It is then seen that the 
adipose coat has considerably increased. 

It will not suffice to recognise the existence of muscular atrophy, 
its localization and extent; its invading and progressive tendency 
should also be determined. An attempt must then be made to estab- 
lish its place in nosology. Its interpretation is often a difficult task 
in view of the multiplicity of clinical types. This fact may be seen 
from the following summary, in which the principal cases alone are 
included : 



482 INTRODUCTION TO THE STUDY OF MEDICINE 

1. Circumscribed Amyotrophies of Muscular Origin. — Myositis, 
rheumatism, and contusions of the muscles, especially the deltoid, 
give rise to local atrophies, which are in no wise extensive. 

2. Amyotrophies of Articular, Osseous, and Visceral Origin. — The 
lesions of articulations, from arthritis to sprain, rapidly produce 
atrophy of the muscles concerned in the movement of the affected 
joints. As already referred to (page 181), the question is one of 
reflex atrophy. 

Fractures of the bones produce the same results. Visceral inflam- 
mations are also included among the causes — e. g., pleurisy gives rise 
to atrophy of the muscles surrounding the affected side. 

3. Amyotrophies of Peripheral Nervous Origin. — Section of the 
nerves, neuralgias, and neurites enter into this group. The action of 
these is limited, while in cases of polyneuritis, which are generally 
consecutive to chronic intoxication by alcohol and lead, there is atro- 
phy of the lower extremities, with suppression of the reflexes, and a 
peculiar gait already described as steppage. It is the syndrome 
otherwise called pseudo-tabes. 

4. Amyotrophies of Spinal Origin. — These are far more numerous, 
and are divisible into two groups according as they are confined to a 
region or assume a progressive course. 

Among the former may be cited infantile paralysis, acute spinal 
paralysis of the adult, various diffused myelites, and alterations of 
the meninges, especially hypertrophic cervical pachymeningitis. 

The second group includes progressive muscular atrophy, of which 
the type first known is Aran-Duchenne's type, starting from the 
thenar eminences and progressively invading almost the whole body. 
Allied to this type is syringomyelitis, which is readily differentiated 
by the study of sensibility (absence of thermal sense without anaes- 
thesia). To the same group belong progressive muscular atrophies 
of the scapulo-humeral type (Vulpian), certain unsatisfactorily 
classed types beginning with the trunk or the lower extremities, amyo- 
trophic lateral sclerosis, and labio-glosso-laryngeal paralysis. 

5. Myopathic Amyotrophies. — These resemble the preceding group 
by their progressive course, and are distinguished from them by the 
absence of spinal lesions. Myopathic amyotrophies include the fol- 
lowing types: Duchenne's pseudo-hypertrophic paralysis with two 
subvarieties, the femoro-tibial type of Leyden-Mobius and the scap- 
ulo-humeral type of Erb; progressive myopathies, including the 
facio-scapulo-humeral type of Landouzy-Dejerine, the scapulo-hu- 
meral type of Immermann and Zimmerlein, and the femoro-tibial 
type of Eichhorst, Charcot, and Marie. 

Exploration of trophic disturbances should be completed by exam- 



EXAMINATION OF THE SICK 483 

ining the other parts of the body: the bones, which are sometimes 
affected, and more particularly the skin with its annexa — nails and 
hair. 

The main disturbances have already been referred to — i. e., ery- 
themata and vesicles of the skin, often following the course of a nerve 
and grouped as in herpes; also bullae, pustules, cutaneous sclerosis, 
pigmentary or vasomotor disorders, eschars, and ulcerations, such as 
the perforating ulcer (mal perforant). (Edemas and pseudo-lipomata 
have already been mentioned. Arthropathies, which are so frequent 
in locomotor ataxia, deserve special mention. 

Intellectual Disturbances. — Abeyance of all the intellectual 
functions is designated as coma. When it comes on suddenly, it 
is termed apoplexy. In both cases loss of consciousness may be com- 
plete or incomplete. In the latter instance peripheral excitations 
elicit a vague perception; certain impressions may for a moment 
bring the patient out of his torpidity. 

These two morbid states are readily recognised, but to determine 
their causation is not infrequently a task of difficulty. Etiological 
diagnosis can only be arrived at by taking into account the concomi- 
tant phenomena, and especially the previous disorders which alone 
offer precise information regarding the diseases of which these two 
syndromes are but epilogues. 

Passing over the extreme occurrences, we shall consider the less 
profound disturbances that may be observed. 

Sleep is modified in a great number of diseases. The patient must, 
therefore, always be interrogated with reference to sleep. 

Infections are often from the start attended by insomnia. When 
the patient falls asleep he has dreams and troublesome nightmares. 
The same occur in the course of chronic states, especially in cerebral 
affections, neuroses, and intoxications, notably alcoholism, auto-intoxi- 
cations, and asphyxia of individuals suffering from cardiopathies. 

In children sleep is often troubled with terrible dreams, especially 
those who are predisposed by nervous inheritance, or who suffer from 
gastrointestinal disorders; in the latter case the manifestations are 
of the character of auto-intoxication. 

Sleep, which is nearly always unsatisfactory in neurasthenic pa- 
tients, may be altogether suppressed in the beginning or course of 
mental diseases. 

Disturbances of sleep consist in sudden jerks, which awaken the 
sleeper, and are especially frequent in alcoholism, in the form of 
dreams and nightmares. Dreams of occupation are equally the lot 
of alcoholic subjects. A dream often has its starting point in some 
morbid sensation or pain. Individuals who suffer from disease of an 



484 INTRODUCTION TO THE STUDY OF MEDICINE 

organ often see animals compressing or tearing the diseased parts; 
the results are very distressing impressions and choking. In the be- 
ginning of mental diseases nightmares are frequent, and recur night 
after night with identical characters, and may become the starting 
point of delirious conceptions, if they do not already represent a sort 
of unconscious delirium. 

Tendency to sleep is increased under a great number of circum- 
stances. In the course of infections the insomnia of the first days 
yields later on to somnolency. Finally, in many diseases, convalescence 
is announced by a return of a calm and peaceful sleep contrasting 
with the somnolency of the preceding days. 

Excessive sleep may be sufficiently marked to characterize certain 
morbid states. Such is sleeping sickness, predominant upon the west- 
ern shore of Africa, of which a slight form is observed in Switzerland, 
and described as paralyzing vertigo or nona. Dr. Briquet, of Armen- 
tieres, published a very curious observation which seems to establish 
a certain relationship between sleeping sickness and myxcedema. 

An irresistible tendency to sleep is observed in various patients 
and constitutes a symptom termed narcolepsy. It is of very frequent 
occurrence in dyspeptic and cardiac patients. When it appears, par- 
ticularly after meals, it must always lead to examination of the urine, 
for the reason that it is often the first sign of diabetes. 

Finally, hysterical patients sometimes have paroxysms of sleep, 
in which some authorities include the syndrome known as hysterical 
apoplexy. It is by the study of concomitant manifestations that a 
differential diagnosis can be arrived at. 

Sleep may also be artificially induced, either by medicinal sub- 
stances called narcotics (opium, chloral hydrate, sulphonal, etc.) or 
by various mechanical or physical means. Intense light, a brilliant 
object, a sudden noise, movements repeated before the eyes, and, with 
some individuals, a simple touch, induce a sleep designated since the 
time of Braid as hypnotic sleep. 

Two varieties of hypnotism have been distinguished: a minor 
form, which includes various degrees from light sleep to profound 
sleep, at times accompanied by somnambulism, and a major form, 
occurring only in hysteria. 

The major form of hypnotism has three stages : the lethargic, the 
cataleptic, and the somnambulistic stage. 

In the lethargic state the subject has the appearance of a sleeper, 
but what characterizes this stage is the markedly increased excitabil- 
ity in the nerves and muscles; hence, an excitation, a light pressure 
upon a muscle or a nerve is sufficient to arouse a contracture far out- 
lasting the excitation. 



EXAMINATION OF THE SICK 485 

In the cataleptic state the subject is motionless, but his limbs 
retain all the positions artificially given them. 

In the somnambulistic stage the patient obeys all suggestions. 

Apart from these cases, somnambulism is also observed under 
various conditions. It is characterized by the continuation, during 
sleep, of the activity started during wakefulness, which is carried on 
in an automatic manner. This, for example, is the case with a child 
that gets up and walks with astonishing assurance in the most peril- 
ous places, such as the sill of a window or the roof of a house. 

Akin to somnambulism is ambulatory automatism. An indi- 
vidual departs from home, and a few days later he finds himself 
in a city far away, without being able to understand how he came 
there. 

In all these instances there is double personality: the individual 
forgets in one of the two states what he has done in the other; there 
is a double life. 

Vertigo. — Of the intellectual disturbances, one of the most inter- 
esting is represented by vertigo. It is a subjective phenomenon, a 
sense of instability in space with reference to surrounding objects. 

This sensation often disappears when the eyes are closed, but not 
always ; at times closure of the eyes aggravates the trouble. 

In order to form an idea of the characters of vertigo the physician 
is compelled to depend upon the description given by the patient. 
If, however, an attack be witnessed, certain bodily disturbances are 
observed, evidencing the suffering caused by vertigo. The face is 
generally pale and expresses anguish; the skin is covered with cold 
sweat. If the victim attempts to walk, he staggers, loses his balance, 
and falls; at times he can not help going on in vertiginous move- 
ments until some obstacle arrests him. 

Vertigo is a phenomenon of frequent occurrence. As a transitory 
event, it occurs in the beginning of infectious diseases, in acute intoxi- 
cations, and particularly in inebriation; it may be brought on by 
mechanical agents : Seasickness and swinging are familiar exciting 
causes. However, individual predisposition must also be admitted, 
since everybody does not experience giddiness under the conditions 
named. 

Vertigo is also met with in the course of organic affections, espe- 
cially in gastric derangements, and in arteriosclerosis, of which it 
often represents an early symptom; it is very frequent in nervous 
diseases, such as tabes dorsalis, multiple sclerosis, exophthalmic 
goitre, and neurasthenia. Moreover, it may assume a character suffi- 
ciently marked to characterize a special morbid state — i. e., Meniere's 
vertigo. 



486 INTRODUCTION TO THE STUDY OF MEDICINE 

Psychical State. — Continuing the examination of the nervous sys- 
tem, certain derangements must be studied the appreciation of which 
is often a matter of difficulty. 

It is important for the physician to be informed of the patient's 
character and the modifications which it may have undergone. In 
the beginning of most diseases directly or indirectly involving the 
cerebral functions, changes are observed in the affections. In some 
cases there is excessive tenderness, in others indifference. At times 
the patient is subject to paroxysms of exhilaration or of melancholy 
without any motive, or else he falls into a state of apathy or hypo- 
chondriasis. In yet other instances the people around the patient 
notice a change in his temper, which becomes strange and fantastical; 
he has " fits " of anger which he did not have before. As an illustra- 
tion, we may cite the example of a child that, in the beginning of 
tubercular meningitis, and before all other manifestations, presents 
psychical changes which sometimes lead the physician to predict the 
imminence of morbid phenomena. 

Psychic modifications may also affect the moral qualities, as evi- 
denced by a tendency to mendacity, loss of moral sense, and sexual 
perversions. Actions considered as criminal are at times nothing 
more than the first manifestations of mental derangements; their 
real character is recognised only after the mental disease becomes 
clearly manifest. 

At the onset of certain mental diseases, and more particularly of 
general paralysis, the subject exhibits an extraordinary activity well 
in contrast with his previous quietude. Interpretation is very deli- 
cate when a man is seen to conceive schemes and execute them skil- 
fully, or to throw himself into an enterprise often with success in 
the beginning, or produce at times very remarkable works. Soon, 
however, defective points appear, which gradually increase and no 
longer leave the slightest doubt in the mind of an attentive observer 
as to the nature of the phenomena. 

A great number of persons present derangements which are mostly 
stigmata of degeneration, and which consequently deserve the close 
attention of the physician. They are divisible into two groups: im- 
pulsions and phobias. 

Impulsions bring certain individuals to the performance of acts 
which may simply be strange, or may border on insanity. For exam- 
ple, they can not help counting their steps in walking, or counting the 
windows on the streets which they pass through; others repeat the 
acts they see (echokinesia) or the words they hear (echolalia) ; yet 
others are at times compelled to utter coarse words obviously unsuit- 
able to their education or habits (coprolalia). 



EXAMINATION OF THE SICK 487 

By the term phobias are designated certain mental disturbances, as 
expressed by unjustifiable and at times childish fears. The dread is 
so intense that it prevents the sufferer from passing through a public 
square (agoraphobia), or from remaining in a closed room (eleithro- 
phobia), or from touching certain objects. Similar to these phobias 
is the insane disposition of doubting, which is sometimes sufficiently 
powerful to prevent an otherwise sane individual from practising 
certain professions. The case of a physician is sometimes cited who 
had to give up his art because of a constant dread of making a mis- 
take in his prescriptions. 

Delirium. — An individual is in delirium when his sensations do not 
correspond to external objects; when his ideas do not correspond to 
his sensations; when his judgment and determination do not corre- 
spond to his ideas, or when his ideas, judgment, and determination 
are independent of his will (Esquriol). 

Following Ball and Ritti, delirium may be divided into lunatic and 
nonlunatic. 

Nonlunatic delirium is observed in infections, intoxications, and 
certain cerebral diseases. 

In its mild forms delirium is simply dreaming in a state of 
half sleep. In a little more advanced stage the patient has hallu- 
cinations; he often attempts to rise, to run away, either to escape 
from imaginary enemies or to respond to calls he believes he hears, 
or to advance toward objects he believes he sees. In its most violent 
forms, delirium is expressed by incessant agitation, cries, and mis- 
directed movements. 

Without dwelling upon these varieties or their causes, it will suf- 
fice to cite as examples the generally calm delirium of typhoid 
patients; the noisy agitation of alcoholics (delirium tremens), which 
is so often occasioned by pneumonia, the noisy and tumultuous de- 
lirium observed in cerebral rheumatism ; the delirium of convalescents, 
of starvation, of cardiac and tubercular patients, and the delirium of 
puerperal women, which is frequently connected with albuminuria. 
The organic lesions, especially those of the liver and kidneys, play an 
important role in the causation of delirium by favouring auto-intoxi- 
cation of the organism. 

Lunatic delirium may be total or partial. When total, it is 
characterized by disorder of all the psychic faculties. Of this, 
two clinical forms have been recognised: the maniacal form, re- 
markable for the exaltation, and the melancholic form, marked 
by persistent depression of spirits. When these two forms follow 
each other, then circular insanity is said to be present. Finally, 

under the name of mental confusion have been described cases 
32 



488 INTRODUCTION TO THE STUDY OF MEDICINE 

in which all ideas are confounded and dissociated ; speech is 
incoherent and all sensations and perceptions are defective or 
inexact. 

Partial lunatic delirium consists in disturbance of one or of sev- 
eral psychical functions. It may aifect the sensations, the thoughts, 
the sentiments or action. 

Delirium of the senses includes illusions and hallucinations. 

Illusion is belief in an image not corresponding to the sensation 
perceived. 

Hallucination is that state of the mind in which the conceived 
image does not correspond to any sensation. 

In the former case the object exists and sensation is real; in the 
latter, both object and sensation are absent. Thus, for example, a 
patient sees a dog and takes it for a fantastic animal. This is 
illusion. He hears the throbbing of his arteries and believes that he 
hears the discharges of electrical machines : this, too, is an illusion. 
These two illustrations give an idea of the two varieties of illusions 
that can be admitted: One originates from an external impression; 
the other from an internal sensation. 

There are hallucinations of the senses and general or special 
sensibility, particularly the genetic sensibilit} r , without the existence 
of any external or internal excitation to account for their develop- 
ment. 

The deliriums of intelligence are extremely varied and may be 
divided into eight groups (Ball and Eitti). They are (1) ideas of 
satisfaction, greatness, and fortune; (2) religious ideas; (3) erotic 
ideas; (4) ideas of persecution; (5) ideas of humility and despair; 
(6) hypochondriacal ideas; (7) ideas of corporeal transformations, 
which consist in the patient's belief that he has changed his sex or 
has been transformed into an animal or vegetable; (8) delirious 
ideas with conscience, including insanity of doubting, hypochon- 
driasis, phobias, and impulsions. 

Impulsion leads to insanity of action. In contradistinction to this 
form should be placed those cases in which all action becomes impos- 
sible, either because the patient no longer has the desire or the 
strength to act, or because he is dependent upon some external power 
which arrests him. 

Finally, there is also dementia, which consists in the loss of the 
mental faculties. This state is always an acquired one, while idiocy 
is always congenital. 

Troubles of Speech. — The disorders in making use of signs, whether 
for expressing or for understanding the ideas and feelings, are called 
disorders of speech or language. 



EXAMINATION OF THE SICK 



489 



Bloeq and Onanoff, from whom we borrow the definition above 
given, divide the disturbances of speech, or asymbolia, as follows : 



Forms. . . . Apraxia. 

~ a • • ( Receptive. 

Gestures. Ammna j __ , r 

( Motor. 



Sounds 



Lalopathy 



Dysphonia . 



Dysphasia 
. (Aphasia). 



Amusia 



Dyslalia. 

Dysarthria. 

_ . i Word blindness. 

Receptive, j A}exia> 

( Aphemia. 

Motor \ A . . 

( Agraphia. 

( Sensory amusia. 

P ' ( Musical alexia. 

/ True motor amimia. 

Motor ... -I Musical amimia. 

( Musical agraphia. 



Notwithstanding their considerable number and complex appear- 
ance, these various forms of asymbolia are easily kept in memory and 
readily recognised. 

Apraxia is a disturbance of appreciation of geometric forms. The 
patient does not recognise the objects he sees and makes use of them 
for purposes for which they are not intended. For example, he takes 
a plate for a saucepan and places it upon the fire. 

Amimia means forgetting the sense attributed to gestures. At 
times the patient can not understand the gestures performed by oth- 
ers: this is receptive amimia; at other times he is unable to per- 
form them correctly: this is motor amimia; he will shake his head 
from right to left to say yes, and from above downward to say no. 

The disorders of phonetic language are more important. They 
are called lalopathy when they bear upon the speech. Lalopathy may 
result from some difficulty in the formation of sounds (dysphasia), 
either by reason of a lesion in the phonal apparatus, tongue, lips, or 
larynx (dyslalia), or by reason of nerve lesions preventing the regular 
play of the same parts (dysarthria), as occurs in general paralysis 
and multiple sclerosis. 

Aphasia can no longer be defined to be the loss of articulate 
speech. It is absolutely necessary to introduce a fundamental divi- 
sion into its study. In fact, there is a receptive or sensory aphasia, 
in which the patient does not understand one of the forms of articu- 
late language. When he has become incapable of apprehending the 
sense of words, although his auditory apparatus is intact, he is said 
to suffer from word deafness. When he is incapable of reading with 
an intact visual apparatus, he is said to be affected with alexia. The 
latter is divided into two varieties: letter blindness, in which the 



490 INTRODUCTION TO THE STUDY OF MEDICINE 

patient no longer recognises the letters, and word blindness, in which 
he no longer understands what word is represented by the association 
of the letters. 

In motor aphasia the victim is no longer able to employ the con- 
ventional signs of language. At times he loses the use of the signs of 
speech (spoken language), this being aphemia, or aphasia properly 
so called; at other times he is incapable of expressing his thoughts 
by writing: this is agraphia. 

Finally, introducing into the study of the musical faculty divisions 
analogous to those admitted for language, a receptive or sensory 
amusia and a motor amusia have been described. Sensory amusia in- 
cludes the true sensory amusia in which the patient no longer distin- 
guishes sounds, and musical alexia, characterized by inability to read 
the notes. Motor amusia comprises motor amusia, properly so called, 
when the patient can not sing; musical amimia, when he can not 
play upon an instrument, and musical agraphia, when he can not 
write the notes. 

We can not dwell upon the numerous clinical forms observed, 
which result either from association of various manifestations or 
from the variable intensity of the disturbances. 

When the question is one of aphasia, it is easy, after having deter- 
mined the variety, to recognise the part of the brain affected. It will 
be remembered that the seat of aphemia is in the third cerebral con- 
volution; word blindness is localized in the angular and inferior 
parietal gyri on the left side, word deafness in the middle part of the 
first temporal convolution, agraphia at the foot of the second frontal. 
This last localization is the least certain. 

It is also possible to determine whether the lesion is seated at or 
beneath the cortex. To this effect the patient is asked to indicate 
upon his fingers the number of syllables contained in each of the 
words which he can not pronounce. If he succeeds, the lesion is sub- 
cortical. This is Lichtheim's sign, the value of which, however, is 
still in dispute. 

Finally, the cause of aphasia is to be investigated. 

Aphasia is divided, according to its course, into transitory and 
permanent. 

Transitory aphasia is observed in auto-intoxications, diabetes, 
albuminuria, gout, dilatation of the stomach, and, in children, in the 
course of a simple indigestion. It occurs in some infections, as, for 
example, typhoid fever and malaria. It is often met with in nervous 
diseases. It may at times be caused by anger or emotion. It is espe- 
cially frequent, however, in ophthalmic hemicrania, hysteria, epilepsy, 
general paralysis, and tumours, and, above all, in syphilis of the brain. 



EXAMINATION OP THE SICK 491 

Permanent aphasia is produced by a destructive lesion. It de- 
pends upon cerebral softening, sometimes upon hemorrhage; it is 
often encountered in case of tumours, syphilis, and acute or chronic 
meningitis. 

The preceding study of nervous disturbances demonstrates that 
they may occur in the course of the most varied diseases. On the 
other hand, nervous affections may influence all the other functions. 
It will suffice to recall urinary and genital disorders, the so-called 
nervous dyspnoea, cardiac palpitations, false angina pectoris, secre- 
tory derangements, hemorrhages, hysterical tympanites, trophic dis- 
turbances, and, lastly, the fever which, in a great number of cases, is 
due simply to irritation of the nervous system. 



CHAPTER XXII 
CLINICAL APPLICATION OF SCIENTIFIC PROCEDURES 

Physical procedures — Mensuration — Examination of deep-seated parts — Cathodic 
rays — Spectroscopy — Thermometry — Exploration of the neuromuscular sys- 
tem — Registering apparatus — Chemical procedures — Clinical examination of 
the urine, secretions, and blood — Microscopical examination — Examination of 
the urine, sputa, and blood — Bacteriological examination — Direct examination 
— Cultivation — Serum diagnosis — Animal inoculation — Exploratory punctures 
and incisions. 

Examination of the sick by means of the simple procedures thus 
far indicated suffices to establish diagnosis in the majority of cases. 
Therefore, when the questioning of the patient is completed, and his 
personal and hereditary antecedents have been noted, when his sub- 
jective disturbances have been considered, and all his organs and 
tissues systematically examined by means of inspection, palpation, 
percussion, and auscultation, and when the characters of his secre- 
tions and dejecta, urine, vomited and faecal matters have been ob- 
served, a conclusion should be arrived at. 

It is often useful, however, and at times necessary to supplement 
examination by means of more precise and delicate procedures. The 
latter are very numerous. We shall indicate the principal ones — i. e., 
those which are of real service — among which some, as for example 
thermometry and chemical analysis of the urine, are indispensable. 

Physical Procedures. — The physical procedures most frequently 
made use of clinically respond to three indications : ( 1 ) They aid 
the usual modes of exploration; (2) they serve for the exploration 
of the inaccessible or hardly accessible parts of the organism; and (3) 
they furnish a precise measure of certain acts and phenomena. 

In connection with certain organs, and particularly in reference 
to circulation and respiration, we have shown how they can be ex- 
plored by means of four simple methods — viz., inspection, palpation, 
percussion, and auscultation. 

Inspection and palpation furnish information as to the form and 
size of regions. For greater accuracy the homologous parts are meas- 
492 



CLINICAL APPLICATION OF SCIENTIFIC PROCEDURES 493 

ured by means of a ribbon or string. In order to appreciate atrophy 
of a limb, its circumference is measured and compared with that of 
the healthy side. Care should, however, be taken to apply the ribbon 
to exactly the same region. In the case of the thorax, half of the 
circumference is measured from the spine to the border of the ster- 
num, while deviations are appreciated by means of a string stretched 
from the notch of the sternum to the middle of the pubis (page 431). 

Various apparatus have been invented for the more precise ac- 
complishment of these examinations. Voillez proposed measurement 
of the thorax by means of a metallic tape formed of articulated links, 
called a cyrtometer. For mensuration of the thoracic and abdominal 
regions the calipers of thickness are mostly employed. Baudeloque's 
calipers, which are in general use, consist of two branches measuring 
about 20 centimetres in height. Each branch is made up of a straight 
portion, which is near the joint, and a curvilinear portion. At the 
point of junction a graduated quadrant is found upon which the 
distance between the two terminal parts can be read in centimetres. 

To-day no apparatus is any longer made use of in percussion." 
Auenbrugger, who endowed science with this important mode of ex- 
ploration, practised immediate percussion. With the fingers of the 
hand he tapped directly upon the part to be examined. This pro- 
cedure has given way to mediate percussion, which is practised in 
three manners : ( 1 ) By striking with the fingers of the right hand 
upon one of the fingers of the left hand applied over the part; (2) 
by striking with the fingers upon a small plate (Piorry's pleximeter) 
of metal or ivory, and (3) by striking upon the locality by means of 
a hammer. 

The pleximeter, which is still in use in foreign countries, has been 
almost entirely abandoned in France. Peter's plexigraph, which con- 
sisted of a cylinder upon which percussion was made and which car- 
ried a dermographic pencil at its lower part, has also become obsolete. 
Only the dermographic pencil (a pencil with aniline violet) is fre- 
quently used to trace upon the skin lines indicating the limits of the 
organs and the areas of flat zones. 

Blanchi has of late presented to the profession a very ingenious 
apparatus, the phonendoscope, which enables one to very exactly out- 
line the principal viscera. 

Auscultation, as well as percussion, is generally made without any 
apparatus. The various stethoscopes, however, are still quite fre- 
quently employed. Though useless for the study of the respiratory 
organs, they serve in locating cardiac murmurs and determining their 
propagation. They are indispensable in the exploration of regions 
where the ear can not be well applied. Auscultation of cervical blood 



494: INTRODUCTION TO THE STUDY OF MEDICINE 

vessels, of the femoral artery and abdominal aorta could hardly be 
accomplished without a stethoscope. 

This instrument also serves for the auscultation of the larynx or 
esophagus at the cervical region. It is also employed in auscultating 
the ear. In the case of the organ last mentioned, however, Toynbee's 
otoscope is commonly made use of. It is a simple rubber tube, 70 or 
80 centimetres long, the ends of which are tipped with ivory; one 
end is inserted into the ear of the patient, the other is applied to the 
ear of the physician. The patient is then asked to swallow saliva, 
having the nose and mouth closed, when a crackling murmur, pro- 
duced by the tympanum, is heard. 

It was at one time believed that excellent results would be obtained 
by applying for auscultatory purposes apparatus capable of re-enforc- 
ing sound. The microphones employed to this end have not, however, 
afforded any advantages. 

Exploration of Deep-seated Parts. — One of the simplest instru- 
ments for the exploration of deeper parts is the tongue depressor, 
which may be replaced by a spoon, permitting examination of the 
pharynx, tonsils, and base of the tongue as far as the epiglottis. 

With the same object in view, speculums are used which render 
possible inspection of canals naturally closed. These instruments are 
cylindrical or conical tubes which are introduced into the canals, or 
apparatus with valves are introduced closed, and when opened they 
dilate the parts to be examined. 

For examination of the vagina and cervix uteri either cylindrical 
specula, with or without solid cylinders, which facilitate introduction 
and are drawn out when the instrument is in its place (Recamier's, 
Dupuytren'sj Mademoiselle Boivin's, and Fergusson's speculums), or 
specula with valves are made use of. Of the latter, the one most com- 
monly employed is the bivalve speculum of Cusco. It is also possible 
to explore the organs by means of a single valve ( Sims' s speculum). 

These apparatus bring to view the state of the vagina (for this 
canal Sims's speculum is alone available), and especially the condition 
of the cervix uteri. 

Analogous specula are used for exploration of the rectum, nose, 
and ear. 

For the nasal fossae a small bivalve speculum is generally em- 
ployed ; for the ear, a small tube with an enlarged end. If the organ 
to be explored is more deeply seated, or if it is situated at the end of 
a sinuous canal, recourse is had to apparatus which bring it into view 
by reflected light or by transparency. In the first case, mirrors are 
made use of. The luminous rays coming from without are sent toward 
the organ, and the intensely lighted image becomes visible upon the 



CLINICAL APPLICATION OF SCIENTIFIC PROCEDURES 495 

mirror. According to this very simple principle are constructed the 
laryngoscope, which, when introduced into the fundus of the throat, 
permits exploration of the larynx; the rhinoscope, which brings to 
view the posterior orifice of the nasal passages; the ophthalmoscope, 
which shows the fundus of the eye, and the endoscope, which enables 
parts hidden behind a narrow canal, and especially the bladder, to be 
appreciated. 

When the canals are too long or too sinuous to allow the use of 
mirrors, the cavities are lighted and seen by transparency through the 
walls. To this end small electric lamps are used which are lighted 
after introduction into the organ to be examined. This method has 
been resorted to especially for exploration of the stomach. 

There are a great number of instruments which, through the tac- 
tile sensations they produce, furnish information as to the state of 
various organic canals or passages. Their use constitutes a method 
called catheterism, consisting in the introduction of rigid or flexible 
sounds, and in the appreciation of the state of the parts from the 
resistance experienced in performing the exploration. In this manner 
the urethra, ureter, uterine cavity (hysterometer), rectum, esophagus, 
and the lachrymal canal may be catheterized. A sound may also be 
introduced into the Eustachian tube; in this case, however, the end 
of the instrument alone is engaged in the orifice of the tube; the 
exploration must be completed by insufflation of air, which immedi- 
ately escapes through the external ear if the drum is perforated. 
To this end air may also be injected into the nasal cavities by means 
of a rubber pump, while the patient swallows saliva, having the nose 
and mouth closed. This is what is known as Politzer's procedure. 

Catheterism is also employed for the examination of pathological 
canals. Stylets and sounds, when introduced into fistulae, reveal their 
state, length, direction, and termination. 

Finally, catheterism of the internal organs has also been practised 
in some instances. After a laparotomy a sound has been introduced 
into the biliary passages. 

Of late, since Eoentgen's discovery, a new method has been in- 
vented. The human body has been explored by passing through it 
cathodic rays and by utilizing either photographic proofs or fluoros- 
copy. 

This procedure renders considerable service in the detection of for- 
eign bodies; it not only permits discovery of their presence, but it 
enables recognition of their exact situation and greatly facilitates sur- 
gical intervention. This mode of exploration is also available in the 
case of concretions formed within the organism, especially for the 
investigation of vesical calculi. Moreover, it renders service in osseous 



496 INTRODUCTION TO THE STUDY OF MEDICINE 

and articular affections, and in fractures and traumatic dislocations. 
It is of less importance in internal pathology; it has, nevertheless, 
revealed the presence of aneurisms and furnished data in reference to 
pleural exudations, and particularly with regard to the state of the 
lungs when incipient tuberculosis is suspected. 

The use of spectroscopy is one of the most interesting applications 
of light to clinical purposes. Henocque has well pointed out the 
great benefit to be derived from this mode of exploration. He has 
directed the construction of an apparatus which can be applied to the 
surface of the thumb and permits the study upon the living subject 
of the rapidity of the reduction of hemoglobin. It suffices to place a 
ligature at the base of the phalanx; under normal conditions, at the 
end of from thirty to a hundred seconds, the hemoglobin is reduced, 
and the two dark absorption bands given by it in the spectrum dis- 
appear. 

Weighing. — Another method derived from physical sciences is util- 
ization of the various procedures of mensuration of phenomena. 

In the first place, among simple procedures the balance may be 
mentioned. It is impossible to exaggerate the advantage which can 
be obtained by causing the patients to be frequently weighed. In the 
course of chronic diseases, especially in pulmonary tuberculosis, vari- 
ations in the weight furnish important data, and oftener and better 
than any other procedure enable one to judge whether the patho- 
logical process is improving or being aggravated. 

With the newborn weighing is indispensable. The infant must 
be weighed in order to determine whether it is growing. During the 
first months growth should amount to 20 or 25 grammes daily. If 
the child gains less than this, it is due to defective alimentation, or 
to the fact that the nurse is not a good one, or the feedings are not 
separated by well-advised and regular intervals, or the amount of 
milk ingested is too great or too small. In such instances the infant 
should be weighed before and after each nursing; the increase in 
weight should amount to 80 or 100 grammes. 

Thermometry and Calorimetry. — Another proceeding as simple and 
important as the preceding one is the study of temperature. 

In studying organic heat, four points may be taken into consid- 
eration : peripheral temperature, central temperature, temperature of 
certain organs or regions, and the heat dissipated. 

Temperature is determined by means of small thermometers grad- 
uated generally between 30° and 45° C, or 95° to 110° F. Except 
in certain rare cases, central and peripheral temperatures follow a 
parallel course. Exploration of one of them is commonly regarded 
sufficient. When peripheral temperature is looked for, the thermom- 



CLINICAL APPLICATION OF SCIENTIFIC PROCEDURES 497 

eter is placed in the axilla or in the groin, while for central tempera- 
ture it may be put in the month or beneath the tongue ; in the latter 
case, however, the evaporation produced by the breathed air inter- 
feres with the results. It is preferable to introduce the instrument 
into the rectum or vagina. In children, rectal temperature should 
always be taken. 

In febrile diseases the temperature is usually taken morning and 
evening. In the majority of instances two daily explorations are 
sufficient. In case of grave fevers, however, thermometry must be 
practised at shorter intervals. In the hospital of Porte d'Aubervil- 
liers, which is devoted to infectious diseases, the temperature is taken 
every three hours, and from this is derived guidance for the treatment 
with cold baths. 

It will not suffice to learn each day the state of temperature; the 
daily variations must be compared. The course of the febrile move- 
ment is of the highest importance for diagnostic and prognostic pur- 
poses. It is therefore necessary to record the temperatures each 
day. To facilitate this task, the graphic method is resorted to quad- 
rilaterally. Ruled charts are used, the vertical lines corresponding 
to days and the horizontal lines to thermal degrees. In recording 
the figures upon the chart a curve is designed, a glance at which 
permits recognition of the daily modifications in the febrile process. 
The various types have already been referred to in connection with 
the evolution of infectious diseases (page 369). 

Local thermometry furnishes indications of particular interest 
from the standpoint of pathological physiology, but it has not entered 
into everyday practice. The same is true of calorimetry. It would, of 
course, be interesting to know the quantity of heat emitted by a pa- 
tient, but the apparatus are cumbersome and expensive; they often 
give information lacking in precision, and are not yet available for 
ordinary clinical purposes. 

Exploration of the Neuromuscular System. — A great variety of 
apparatus has been invented for mensuration of various functions. 
The apparatus are divided into two groups: some are simply instru- 
ments of exploration, others record graphically the activity of the 
parts. 

In the first place, general sensibility and the organs of sense may 
be investigated. 

Examination of sensibility is satisfactorily made without the as- 
sistance of apparatus. There exist, however, serviceable instruments, 
such, for example, as the cesthesiometrical needle of Beaunis, consisting 
of a needle supporting a plate which is charged with weights. Weber's 
O3sthesiometer, which is more commonly used, is essentially composed 



498 INTRODUCTION TO THE STUDY OF MEDICINE 

of two hands, of which one is fixed and the other movable upon a 
graduated quadrant. It serves to determine at what distance two 
impressions become distinct or fuse — i. e., give two sensations or a 
single one. Liegeois has invented an analogous apparatus for the 
appreciation of thermal sensibility. The two points are connected 
with two reservoirs, which are filled with liquids of different tem- 
peratures. 

A certain number of instruments are also employed for examina- 
tion of the organs of sense. There are olfactometers for testing the 
smell, which are useful in physiology, but too complicated to be uti- 
lized in medical practice. 

For testing the taste, sapid substances are placed upon the tongue ; 
a faradic current is at times resorted to, which normally gives rise 
to an acid sensation. For testing the hearing, a tuning fork is gen- 
erally made use of. For the visual apparatus recourse is had to very 
different procedures, according to the particular exploration required. 

Visual acuity is appreciated by means of charts with printed char- 
acters of various sizes. For the study of colours, disks or papers of 
various colours are used. Finally, although the field of vision may 
be appreciated by the simple procedures already described (page 477), 
a special apparatus, the campimeter, is often made use of for greater 
precision. It is a moving circle; the patient takes his position in 
the centre, gazes at a point, and indicates when he perceives and 
when he ceases to see a small white paper carried upon the circle. 
The division to which the limit of perception corresponds is then 
noted. 

In exploration of muscular contractility the points to be appre- 
ciated are whether the power is preserved and whether the muscle 
contracts in a normal manner. 

Muscular power is tested by means of the dynamometer. The in- 
dividual exerts pressure upon a metallic ellipse bearing at its centre 
a needle which records the number of kilogrammes equivalent to the 
contraction. 

The investigation of contractility requires the use of electric cur- 
rents. Both continuous and interrupted currents should be succes- 
sively applied to the muscles and nerves. 

It is well to determine beforehand the resistance of the body to 
the passage of the current; this is readily established by noting the 
number of millimetres deviation of the needle of the galvanometer 
for a given galvanomotor force. 

For exploration of muscles the larger electrode is placed upon the 
sternum or the spine ; the other, the so-called labile electrode, is car- ; 
ried around upon the various parts. It must first be determined 



CLINICAL APPLICATION OF SCIENTIFIC PROCEDURES 499 

whether the muscular contractions produced by a given current are 
equal to, less, or greater than those observed in a physiological state. 
This point may readily be determined by comparison with a healthy 
subject or with those muscles of the patient which have remained 
intact. 

The qualitative modifications should next be investigated. It is 
to be borne in mind that, under normal conditions, effects vary with 
the pole considered. A weak current produces a contraction of closure 
at the negative pole. If the intensity increases, the positive pole 
causes a contraction which, although milder, outlasts closure as well 
as opening. Finally, a very strong current causes a contraction of 
opening at the negative pole, but at the moment of closure a real 
tetanization occurs. These various results are expressed by the fol- 
lowing formula : * 

AnOZ 
KaSTe> >KaOZ 

AnSZ 

In a great number of neuromuscular alterations the formula is 
reversed. Reaction of degeneration (Ed) is then said to exist: 

KaSZ 

AnSZ> >AnOZ 

KaOZ 

In grave cases galvanic contractility disappears : AnSZ is the last 
persisting reaction. 

While these changes in galvanic contractility are produced, faradic 
contractility of the nerve or muscle diminishes or even disappears. 
In order for Ed to be complete the two orders of modifications must 
coexist. 

Sensitiveness to faradic currents is diminished in atrophies and 
suppressed in neurites, acute diffuse myelitis, and infantile paralysis; 
it is increased in certain affections, such as tetany. In Thomsen's 
disease the mildest faradic stimulation of the muscles gives rise to 
contracture. 

Mensuration of Cavities. — It is useless to dwell upon the various 
instruments designed for the measurement of the capacity of appa- 
ratus and reservoirs. Eecourse is at times had to spirometers to appre- 
ciate the respiratory capacity of the lungs. To this end, the appa- 
ratus of Hutchinson and Wintrich, or that of Boudin are made use of. 
The former essentially consists of a bell plunged into a reservoir full 
of water and kept in equilibrium by a counter weight. The patient 

* The meaning of the letters is as follows : Ka, Cathode or negative pole ; An, 
anode or positive pole ; S, Schliessung or closure ; 0, Oeffnung, opening or rupture 
of the current ; Z, contraction ; Te, tetanic. 



500 INTRODUCTION TO THE STUDY OF MEDICINE 

executes inspiratory and expiratory movements through a rubber 
tube into the bell, the displacements of which, under the influence 
of the changes in pressure, are indicated by a moving index. Bou- 
din's apparatus consists of a rubber bulb into which the patient ex- 
pires : the bulb swells in proportion to the volume of air sent into it, 
and its amplification is appreciated by means of a graduated lever 
which it raises. 

Finally, the subject may also be instructed to breathe into a 
manometrical tube or pneumomanometer ; the oscillations of the mer- 
cury indicate the force of respiratory pressure. 

Registering Apparatus. — The recording apparatus employed in 
clinical examination are very numerous. They are constructed so as 
to trace upon a moving paper the movements produced in different 
parts of the organism. According to the organ explored, the inscrip- 
tion is made either directly by means of a lever displaced by the mov- 
ing organ, or indirectly by aerial transmission. In the latter case, the 
moving organ compresses Or distends an elastic bulb communicating 
with another bulb provided with a registering stylet; the inscription 
is made upon a more or less rapidly moving cylinder. 

The graphic method has been applied especially to the study of 
muscular contractility, movements of the thorax, and the cardio-vas- 
cular apparatus. 

The muscles may be examined as to their power and manner of 
contraction. 

There are registering dynamometers or dynamo graphs in which 
muscular effort is expressed by the tracing of a line. The apparatus 
most interesting from this standpoint is the ergograph. Suppose the 
upper limb is to be explored. It is attached to a table, the anterior 
surface directed upward. The hand or, still better, a single finger 
is left free, to which is fixed a ring provided with a thread passing 
over a pulley and attached to a plate charged with weights. The 
patient is instructed to regularly execute movements of flexion and 
extension; the weights, constantly raised and lowered, impart to the 
pulley successive rotations in reverse directions ; the pulley, being pro- 
vided with a stylet which records the movement upon a cylinder, gives 
a tracing, which becomes more and more irregular as fatigue in- 
creases. 

By means of similar procedures — for example, by uniting the 
segments of a limb with exploring drums — it is possible to study the 
mode of muscular contraction either under the influence of will or of 
excitants, especially of electrical stimulation. 

It is often useful to record anomalous movements — e. g., the con- 
tractions of tics, paramyoclonus, and tremors. In the latter case the 



CLINICAL APPLICATION OF SCIENTIFIC PROCEDURES 501 

graphic method can render very great service. It fixes the characters 
of the tremors, and at the same time it unveils those that are simu- 
lated : after a little while irregularities are produced betraying the 
fatigue of the individual. 

The graphic study of the respiratory apparatus is made by means 
of elastic bulbs placed upon the thorax. At each respiration these 
bulbs, which are fixed by a circular inextensible string, are compressed 
or distended, while the change in pressure produced in their interior 
is transmitted to a recording drum. Most of these apparatus, styled 
pneumographs, indicate the total expansion of the thorax. By using 
two separate bulbs, however, and two independent threads fixed 
upon the spinal column, a separate tracing for each half of the thorax 
can be obtained. This apparatus, designated as bilateral stethograph, 
furnishes exact indications as to the extent and form of the move- 
ments of each half of the thorax and reveals the slightest differences. 

The graphic method is especially serviceable in the study of the 
circulatory system. 

The movements of the heart can be directly registered by means 
of the cardiograph, which is essentially formed of a bulb provided 
with an exploring button communicating with the organ through the 
chest wall. 

The arteries are more frequently explored. The sphygmograph is 
applied to the radial artery. The movements of the vessel are trans- 
mitted to a lever and are directly recorded upon a sheet of paper, 
which moves onward by virtue of a clock mechanism. In view of the 
fact that this apparatus furnishes somewhat varied indications ac- 
cording to the manner in which it is applied, the sphygmometro graph 
has recently been proposed. A very ingenious contrivance renders it 
possible to appreciate the pressure exerted by the apparatus upon 
the artery; the tracings are more exact, but the instrument is com- 
plicated and difficult to employ. 

We shalr not dwell upon the numberless other applications of the 
graphic method; various apparatus have also been made use of for 
exploration of many other organs. Thermometers have also been 
constructed which register the temperature of the body in a continu- 
ous manner. Finally, there is every reason to hope that by means 
of chronophotography and cinematography results as important will be 
obtained in pathology as have already been arrived at in physiology. 
Especially in nervous diseases attended by disturbances of the gait, 
the study of photographs taken successively at short intervals is evi- 
dently liable to lead to interesting deductions. 

Chemical Pkocedukes. — Chemical analysis furnishes clinical re- 
sults of considerable importance. It is applied particularly to the 



502 INTRODUCTION TO THE STUDY OF MEDICINE 

study of normal and pathological humours, such as the urine; less 
frequently to the gastric juice and exceptionally to the blood or acci- 
dental fluids, such as those of ascites, pleurisy, cysts, etc. 

Chemical Analysis of the Urine. — Examination of the urine should 
be made in all cases and in all patients. When complete information 
is desired, long and delicate manipulations are required; in practice, 
however, there are certain investigations within the reach of all physi- 
cians which should never be neglected. 

In the first place, the amount of urine voided in twenty-four 
hours is to be determined. For this purpose the patient should be 
instructed to collect his urine during a day and a night. The colour 
is readily appreciated; for exactness, recourse is had to the coloured 
scales published by ISTeubauer and Vogel. It is equally easy to deter- 
mine the transparency, consistence, odour, presence of filaments, sub- 
stances in suspension, or the existence of sediment. Furthermore, it 
is always well to ascertain the reaction and density. 

If the urine is turbid, the cause of this anomalous state must be 
sought for. It is to be remembered that in most cases turbidity is 
due to the presence of mucus, pus, uric acid, urates, or excess of phos- 
phates. Mucus is precipitated by acetic acid; pus forms a curdled 
mass by the addition of ammonia ; uric acid and urates are dissolved 
by heat ; phosphates become soluble by the addition of acetic acid. 

When the urine is more intensely coloured than natural, the cause 
must be determined. Blood imparts to it a red or brownish hue ; 
microscopic examination then demonstrates the presence of red blood 
corpuscles. In case of hemoglobinuria, recourse is to be had to the 
spectroscope, which shows the two characteristic absorption bands. 
The same instrument permits the recognition of urobilinuria. Final- 
ly, intense colour is often referable to the presence of biliary pig- 
ments. These are detected by Gmelin's test. A small amount of a 
mixture of fuming and ordinary nitric acid, in the proportion of 1 to 
4, is poured into the tube containing the urine. When carefully 
poured along the wall of the tube, the denser acid falls to the bottom, 
and at the point of contact of the two fluids there is formed a series 
of superposed rings — green, blue, violet, and yellow. Only green is 
characteristic. In case the reaction is not sufficiently definite, the 
pigment should be dissolved by means of chloroform, and the latter, 
after having been decanted, should be treated with nitric acid. In 
some instances it is well to supplement examination of icteric urine 
by an inquiry as to the presence of biliary acids. For this purpose, 
Pettenkofer's test is employed. The addition of a certain amount of 
a solution of cane sugar, and then of a few drops of sulphuric acicl, 
produces a violet-purple colour. Instead of pouring the acid upon the 



CLINICAL APPLICATION OF SCIENTIFIC PROCEDURES 503 

urine, it is preferable to deposit a few drops of it upon a filter paper 
saturated with the icteric urine, to which sugar has been added. 

These various tests are of practical interest; there is, however, 
an examination of greater importance which is required in all cases — 
namely, that for albumin and sugar. 

For albumin, a trace of acetic acid or vinegar is added to the 
urine and then heated ; or nitric acid is poured into the tube. Since 
the time of Gubler it is customary to pour the acid along the wall of 
the tube ; the albumin, when present, forms above the acid an opaque 
white layer, and above this a ring of uric acid or urates appears. This 
procedure (the contact method with nitric acid) is insufficient. It is 
better to resort to more delicate tests. Tauret's test (iodo-mercuric 
solution) is altogether commendable. It is applied in the following 
manner: A small quantity of urine is poured into a test tube; the 
reagent is then added. If the urine remains clear, it can be decided 
that no albumin is present; if it becomes turbid, it must be sub- 
mitted to heat before giving a decision. Three occurrences are then 
possible: (1) The precipitate may increase; (2) it may unite in the 
shape of small flocculi, and the liquid becomes clear; or, lastly (3), 
it may be dissolved by heat and reappear when cooled. In the first 
case, non-retractile albumin (Bouchard) — i. e., globuline — is pres- 
ent ; in the second case, albumin is said to be retractile ; it is a serine. 
Finally, when the specimen is cleared by heat, it is understood that 
the precipitate is due to peptone or alkaloids, and, in fact, questioning 
almost always proves that the patient has taken quinine. 

The method just indicated is a most important one, because it re- 
veals at the same time the presence of albumin, peptones, and alka- 
loids. It is objected that a precipitate may be produced by mucin; 
the error, if it is ever liable to occur, can be avoided by treating the 
urine with acetic acid, which precipitates mucus in the absence of 
heat. When pus is present, the urine is also albuminous; in this 
case the diagnosis is made in view of the turbid, opalescent, or milky 
appearance of the fluid, and by the use of ammonia, which produces 
a viscous, ropy, and even compact mass. 

The quantitative analysis of albumin is clinically made by means 
of Esbach's tube (albuminometer), an inexact procedure, but suffi- 
cient for practical purposes. 

We shall not dwell upon the examination for sugar and its quan- 
titative estimation; the procedures are indicated in all treatises on 
chemistry and urology. In clinical examinations it generally suffices 
to look for sugar by Fehling's solution. For its quantitative analysis, 
Bouchardat's method is employed in the following manner: The 
specific gravity is found and the last two figures are multiplied by 2; 
33 



504: INTRODUCTION TO THE STUDY OF MEDICINE 

the product is then multiplied by the quantity voided in twenty- 
four hours, and from the final product are subtracted 60 grammes, 
representing the other elements of the urine. It is hardly necessary 
to say that the result is but approximative. 

Whenever glycosuria is met with, ethyldiacetic acid is always to 
be sought for. A few drops of perchloride of iron are poured into a 
tube containing the urine. The reagent, being heavier, goes to the 
bottom and assumes a characteristic colour — that of Bordeaux wine. 
A cause of error to be avoided is the presence of antipyrine, which 
gives an almost identical colour. If the patient has ingested sodium 
salicylate, the perchloride gives an intense violet colour which is 
quite different from the preceding. 

In brief, clinical examination of the urine requires but a few re- 
agents — viz., nitric acid, Tarnet's reagents, the cupropotassic liquid, 
perchloride of iron, acetic acid, and ammonia. To these may be 
added hydrochloric acid, very useful for the detection of indican. The 
urine heated with this reagent becomes violet in colour. 

Supplemental information is only exceptionally required. Quan- 
titative estimation of urea, uric acid, chlorides, phosphates, and more 
rarely of sulphates or other substances, as the case may be, should 
then be made. 

Examination of the urine may also inform us as to the activity 
of certain organs. As has already been stated (page 202), the state 
of the liver can be determined by the study of alimentary glycosuria. 
To appreciate the state of the kidneys, readily detectable substances, 
such as sodium salicylate, potassium iodide, and methylene blue (this 
colours the urine) are administered and then looked for in the urine. 
The urinary elimination is also of service in the study of the gastro- 
intestinal functions. Salol is given to the patient; so long as this 
medicine remains in the stomach the urine contains nothing of a spe- 
cial character; but when salol arrives at the duodenum, it undergoes 
decomposition, and gives off salicylic acid, which is absorbed and elimi- 
nated by the urine, where it is discovered by means of perchloride of 
iron. The motility of the stomach is thus appreciated. 

Analysis of the Secretions and of the Blood. — For examination of 
gastric contents GKinzburg's capsules are sometimes employed. A 
small fragment of potassium iodide is enveloped in a rubber bound 
with fibrine. When the latter is digested by the gastric juice, the 
rubber opens and the iodide, being absorbed, is readily detected in the 
saliva by means of starch and nitric acid. The time elapsed between 
the ingestion of the capsule and the appearance of the reaction indi- 
cates how long gastric digestion lasts. 

More often, however, recourse is had to analysis of the gastric 



CLINICAL APPLICATION OF SCIENTIFIC PROCEDURES 505 

juice, which is collected by means of a tube after a test meal. The 
procedures made use of are very complex; their main object is to 
appreciate the activity of the hydrochloric secretion and the state in 
which chlorine is excreted. 

The chemical analysis of the sputum is seldom made. It is only 
necessary to know that chlorides abound in the expectoration of pneu- 
monia; that a considerable quantity of cholesterine is met with in 
the same disease, while it is very rare in consumptives ; and that the 
glycogenic substance is encountered in all purulent expectorations. 

The chemical analysis of the blood requires too great quantities 
of the fluid to be practicable. However, with 2 or 3 cubic centi- 
metres of blood some characters of interest may be appreciated — such, 
for instance, as the rapidity of coagulation, and especially the appear- 
ance of the serum, which, instead of being of the normal yellow hue, 
may have a milky look, or be greenish or reddish. The presence of 
bilirubin, hemoglobin, or urobilin in the serum can be recognised by 
means of spectroscopic examination. Finally, an excess of uric acid 
may be looked for by plunging a thread into the fluid after having 
added to it acetic acid in the proportion of 6 drops to 4 grammes. 
Within twenty-four to forty-eight hours the fluid almost completely 
evaporates, leaving upon the thread a deposit of characteristic crys- 
tals. The investigation of uric acid, so important for the semeiology 
of gout, is made more easily with the serum obtained by a vesicatory. 

All these examinations, including that of the density, although 
possible with such small quantities of blood as to be without any 
inconvenience for the patient, are too delicate to enter the domain of 
current practice. The same is true of the analysis of pathological 
secretions or excretions. Chemical examination of vomited or faecal 
matters is very seldom, if ever, undertaken, and is without importance 
unless it be in cases of poisoning. We shall not dwell upon this ques- 
tion, which is completely exposed in treatises on biological chemistry 
and legal medicine. 

Miceoscopic Examination. — Excretions, blood, and at times 
tissues and pathological fluids are submitted to microscopic examina- 
tion, and in this manner the presence in them of cellular or crystal- 
line elements, parasites, and bacteria can be recognised. 

In the case of urine, for instance, chemical examination must 
very often be supplemented by a microscopical study, the latter being 
of considerable importance in appreciating crystalline deposits. The 
blood corpuscles are readily recognised by their characters ; it should, 
however, be remembered that the latter, being decolourized and 
swollen by the fluid, often assume a spherical form. When the urine 
is very alkaline, they are rapidly dissolved in it. 



506 INTRODUCTION TO THE STUDY OF MEDICINE 

The presence of leucocytes is readily recognised: they are met 
with in all urines, but in small numbers ; they are often found in the 
form of small masses in the filaments of chronic gonorrhoea patients. 

Epithelial cells are also nearly always met with. Those coming 
from the bladder possess an irregular appearance, often recalling the 
form of a racket; those derived from the pelvis are pavemental; 
those of the kidneys are cylindrical or cubical. Cells of renal origin 
are not normally found. Under pathological conditions they are 
generally met with, isolated or united, along with cylinders (casts). 
The latter name is given to elongated productions, reproducing the 
form of uriniferous tubules, made up of hyaline or granular masses 
and epithelial cells. 

Finally, microscopic examination likewise reveals the presence of 
spermatozoids in the urine, and, in case of tumour, fragments of nor- 
mal or neoplastic tissues. 

Microscopic examination of vomited matters is seldom made, and 
a little more frequently that of faecal matters. Blood corpuscles, 
leucocytes, epithelial cells, and especially food particles are sought 
for, the presence of the last-named element being dependent upon a 
more or less marked disorder of digestion. 

Microscopic examination is also applied to the semen, to detect 
spermatozoids, and to various exudates, to determine the presence of 
figurate elements in them, particularly of leucocytes. 

Special attention should be devoted to sputa. Microscopic ex- 
amination reveals their nature. The presence of epithelial cells, 
which are often altered and degenerated, is not of great semeiological 
significance. Small mucoid corpuscles, purulent or bloody globules, 
and cylindrical filaments of fibrine are often met with in expectora- 
tions. It is more important to look for elastic fibres, which can read- 
ily be demonstrated by means of acetic acid that leaves them intact, 
after having dissolved the other elements, or by means of eosine, which 
colours them intensely. Their presence means a destructive lesion of 
the lungs — e. g., abscess, cavity, or gangrene. In the last-named affec- 
tion, however, they are often absent, for they can be digested by a 
special ferment originating in the sphacelated lung. 

Sputa may also present to the microscope pigmentary masses and 
various crystals. In cases of putrid bronchitis or pulmonary gan- 
grene, crystals of margarine and of cholesterine, leucine, tyrosine, at 
times ammonio-magnesian phosphates, and, after bronchial hemor- 
rhage, hematoidine are met with. Particular crystals (the so-called 
Charcot-Leyden), occurring under the form of elongated and bril- 
liant octahedrons, are encountered during and after a paroxysm of 
asthma. 



CLINICAL APPLICATION OF SCIENTIFIC PROCEDURES 507 

Examination of the Blood. — The microscopic examination most fre- 
quently practised in clinics is that of the blood. By means of appa- 
ratus that are easily handled the richness of blood in red corpuscles 
can readily be determined. In France, the hematimeters of Potain, 
Malassez, Hayem, and Nachet are commonly made use of. The prin- 
ciple is always the same. A known quantity of blood is diluted in a 
preserving fluid and examined under the microscope in a well-cali- 
bred tube or cell. Under normal conditions the number of red cor- 
puscles per cubic millimetre is from 4,100,000 to 5,000,000. Under 
pathological conditions these corpuscles may increase in number, 
though this is rarely the case. This condition is said to exist when, 
after large losses of liquid, particularly in cholera, the blood is more 
concentrated than is natural. The highest degree of hyperglobulia, 
however, is observed in congenital cyanosis. 

Decreased number of the red blood corpuscles is far more frequent, 
and characterizes anaemic and cachectic conditions. Along with vari- 
ations in number should be decided the qualitative modifications 
which are of greater consequence. The richness in hemoglobin must 
be carefully determined. To this effect various chromometers are em- 
ployed, the simplest among them being that of Hayem. Two small 
cups are fixed upon a slip of glass; one is filled with a dilution of 
blood, the other serves to hold papers of various shades of red. It will 
suffice to find the shade corresponding to the dilution under exami- 
nation, since the papers possess determined values. In this manner 
it may be decided that, in certain anaemias, the defect of the red cor- 
puscles is not in the quantity but in the quality. 

Microscopic examination also reveals the size of the corpuscles, 
which may be larger or smaller than normally, the presence of a 
nucleus (nucleated red corpuscles) in certain cases, and their deformi- 
ties; they retain their biconcave shape, but their borders are often 
irregular and thickened, owing to the presence of pigmentary granula- 
tions. 

Along with red corpuscles are found small elements designated as 
hematoblasts (Hayem). Their numbers are apt to increase suddenly 
after hemorrhages and at the end of acute diseases. They constitute 
one of the elements of the hematic crisis. Finally, globules may be 
seen united and agglutinated by a viscid substance: these are the 
so-called phlegmasic plates. 

The study of the red corpuscles and of hematoblasts may be made 
in a very simple manner, without slaining. The same is true of the 
white blood corpuscles when their number only is to be estimated. 
In other cases histochemical reagents must be resorted to. To-day 
it is not sufficient to simply decide that the number of the white 



508 INTRODUCTION TO THE STUDY OF MEDICINE 

corpuscles is above or below the normal, their variety must also be 
determined — i. e., whether lymphocytes, mononucleated or polynu- 
cleated globules, or oxyphile or neutrophile basophiles are present. 

Microscopic examination also reveals the manner in which coagula- 
tion of blood is effected. The fibrinous network characterizing coagu- 
lation may form too soon or too late. In phlegmasias coagulation 
is delayed, the fibrine has increased, the leucocytes and hematoblasts, 
are more numerous than normally. 

It can be seen by these few examples that examination of the 
blood renders great clinical service. It is always useful, but there 
are two cases in which it is indispensable : when anaemia is present 
or leucaemia is suspected. If the case is one of anaemia, examination 
of the blood is the only means of knowing whether the prescribed 
treatment produces any amelioration. In leucaemia it is impossible to 
make a positive diagnosis so long as the number of white corpuscles 
and their proportion to the red corpuscles are not determined. 

Microscopic examination may detect the presence of parasites in 
the blood, humours, and tissues. 

The filaria and the hematozoon of malaria are those most fre- 
quently found in the blood; the oidium is met with in the mouth; 
the Aspergillus fumigatus and actinomyces in the expectorations. 
Vomited matters and stools of course contain numerous parasites; 
it will suffice to mention the sarcinae of the stomach, the amoebae and 
Anguillula intestinalis, and often the ova of more highly organ- 
ized parasites. Finally, microscopic examination, which is indispen- 
sable for the study of certain skin diseases, and particularly of tinea, 
is also applied to the investigation of parasites in the pus of abscesses 
and in visceral collections. When a fluid is suspected to be of hydatid 
origin, the hooklets, which are of great diagnostic value, must be 
sought for. Finally, when trichinosis is thought of, a small frag- 
ment of muscle, taken by means of a harpoon, must be submitted to 
microscopic examination. 

Bacteriological Examination. — There are three methods for 
the investigation of pathogenic microbes: Microscopic examination, 
cultivation, and inoculation into animals. 

Microscopic examination of the blood affords information in only 
one microbic disease — that is, recurrent fever — in which case Ober- 
meiers spirilla can be seen during a paroxysm. In most other in- 
stances the blood contains no microbes, or too few, if any, to be de- 
tected in a preparation. The anthrax bacillus has indeed often been 
observed in the blood, but examination has then been made in that 
last stage when events of a grave character are present and the micro- 
scopic demonstration has no longer any clinical importance. 



CLINICAL APPLICATION OF SCIENTIFIC PROCEDURES 509 

Microscopic examination 'suffices to determine the presence in 
pus of certain microbes difficult of cultivation, such as the tubercle 
bacillus and gonococcus. It is likewise serviceable in the case of cer- 
tain species with peculiar morphology, such, for example, as strepto- 
coccus and pneumococcus. 

The tubercle bacillus may be sought for in all exudates, especially 
in the expectorations, in the urine, stools, pus, and tissue debris. It 
is, however, to be borne in mind that, while the presence of the 
bacillus is of incontestable diagnostic value, its absence does not 
necessarily imply absence of tubercular lesions. When the microbes 
are very few in number they may escape notice. Hence, in examin- 
ing the urine, care is taken, in laboratories, to first submit the liquid 
to centrifugation in order to bring together the scattered bacilli. 

Microscopic examination is often resorted to for detecting in the 
expectorations the pneumococcus, which is readily recognised by its 
form, consisting of two elements and its capsule; the streptococcus, 
whose appearance under the form of a chain is characteristic ; and the 
bacillus of Friedlander, a rod surrounded with a capsule. In most 
cases the microbes are so very numerous and varied that a simple 
microscopic examination does not warrant a positive conclusion. 
When, for example, it is desired to make examination of a false mem- 
brane derived from the throat, cultivation is indispensable for deter- 
mining its diphtheritic nature. The same method of observation is 
applicable to the differentiation of microbes in faecal matters. 

Among pathological products pus is the most frequently examined 
under the microscope. The pneumococcus, streptococcus, staphylo- 
coccus, tetragenus, and gonococcus are then very readily distinguished. 
The last-named agent has, as is known, a peculiar form, and, unlike 
the other pus cocci, is decolourized by Gram's method. In these vari- 
ous pathological products actinomycetes may also be looked for. 
They are perceptible to the unaided eye when the suspected pus is 
spread over a glass slide, upon which they appear as small, slightly 
elevated granules. If the preparation is treated with picrocarmine, 
they appear under the microscope in the form of rosettes stained an 
intense yellow by the picric acid. 

Cultivation. — The method of cultivation requires a quite compli- 
cated apparatus and special technical knowledge, and, therefore, can 
hardly be made available in ordinary practice. Nevertheless, it is 
often resorted to in various forms of angina. The majority of physi- 
cians are to-day convinced that clinical observation alone is power- 
less to distinguish the diverse varieties of sore throats, and particu- 
larly diphtheria. This statement is exaggerated and has led to mani- 
fest abuses. In reality, two instances are observable. In some cases 



510 INTRODUCTION TO THE STUDY OF MEDICINE 

diphtheritic sore throat presents clinical characters so distinctive that 
doubt is rendered impossible, and the serum treatment should then 
be applied immediately. In the meantime bacteriological examina- 
tion will show whether the diagnosis was right or wrong, but almost 
always it will confirm the clinical diagnosis, and therefore it is not 
indispensable from a clinical standpoint. At other times the sore 
throat, although pseudo-membranous, is so benign that the use of 
serum is not indicated. It is in such cases of medium intensity that 
cultivation renders great service, although attentive examination is 
very often sufficient. However, the clinical diagnosis of diphtheria 
requires long experience and is hard to acquire; hence, many physi- 
cians have adopted the bacteriological method, which appears to be 
simpler. 

For the bacteriological examination of lesions suspected to be diph- 
theritic, the products are placed in a tube of gelatinized blood serum. 
In most cases the diphtheria bacillus develops within twenty-four 
hours and before all other microbes. The mere presence of colonies 
is not, however, sufficient to affirm the bacteriological diagnosis. 
Microscopic examination of the culture is indispensable. 

Cultivation is sometimes resorted to for determining the presence 
of the pneumococcus in sputa* To this effect defibrinated coagulated 
blood is preferably employed. 

The typhoid bacillus is sought for particularly in the faecal mat- 
ters. This is a very delicate procedure and requires long practice. 
The cholera vibrio is more readily discovered: cultivation is done in 
peptonized water, and at the end of twenty-four hours 5 to 10 per 
cent hydrochloric acid is added to the culture, when the red reaction, 
or cholera red, becomes manifest. Although this colour, which is due 
to the presence of indol, may be obtained with other microbes, it 
nevertheless possesses a certain value. 

Cultivation of pus presents nothing special. Cultivation of the 
blood is made either by taking a drop of blood from the finger, or, 
what is preferable, drawing it from a vein by means of a well-sterilized 
syringe. In order to detect a microbe a great amount of blood must 
be sown upon appropriate media. 

Serum Diagnosis. — Another bacteriological method, inaugurated 
by Dr. Widal, seems to render remarkable service. This method is 
based upon the fact that in certain diseases the serum acquires the 
property of agglutinating the pathogenic agent. A few drops of blood 
are therefore taken, and the generally diluted serum is mixed with 
the microbe which is to be studied. If the disease is really dependent 
upon it, the scattered individuals come together in small masses. 
This method, spoken of as serum diagnosis, was first employed in 



CLINICAL APPLICATION OF SCIENTIFIC PROCEDURES 511 

reference to typhoid fever; according to the researches made by Dr. 

Arloing and his pupils, it also appears to be applicable to tuberculosis. 

In brief, bacteriological diagnosis can be conducted in three ways : 

1. Microscopic examination of contaminated parts, which con- 
stitutes an excellent procedure in cases of tuberculosis, recurrent 
fever, actinomycosis, and gonorrhoea, and is often sufficient for the 
investigation of the pus cocci. 

2. Cultivation, which is used especially for detecting the diph- 
theria bacillus. 

3. Serum diagnosis, applicable to typhoid fever. 

Inoculation into Animals. — The last method consists in utiliz- 
ing living animals. It is diagnosis by biological procedures. Recourse 
is had to this method when the microbe can not be detected by direct 
examination or cultivation. Such is especially the case with the 
pneumococcus and the bacilli of glanders and tuberculosis. 

The liquid suspected to contain pneumococci is inoculated into 
a mouse. The animal succumbs within twenty-four to forty-eight 
hours, when its blood is found full of encapsulated diplococci having 
an altogether characteristic appearance. 

The best procedure for the biological examination for glanders 
bacillus is that of Straus. The suspected pus is introduced into the 
peritoneal cavity of a male guinea pig. If the animal does not suc- 
cumb to a peritonitis caused by an accidental microbe, an orchitis 
develops within twenty-four hours, demonstrating the presence of 
glanders. 

The suspicious products of tuberculosis are likewise inoculated 
into a guinea pig. The fact that the period of survival is variable 
and at times very long renders the procedure scarcely practicable. 
Although the development of multiple adenopathies and emaciation 
of the animal suggest tuberculosis within ten days, granulations 
appear in the viscera only a month after inoculation. 

The best means of making a diagnosis of hydrophobia is inocula- 
tion into animals. The autopsy of a rabid dog is negative ; it reveals 
no lesions. Post-mortem diagnosis is, therefore, impossible unless a 
particle of the medulla be inoculated beneath the dura mater of a 
rabbit. Unfortunately, quite a long period elapses, from twelve to 
twenty days, before the symptoms become manifest. 

The toxicity of certain normal or pathological fluids has also 
been studied upon animals. Blood serum or urine has more than once 
been injected. Toxicity of the urine is studied upon rabbits by means 
of intravenous injections; we have already spoken at length of the 
interest of this method, which, unfortunately, is not practical 
(page 200). 



512 INTRODUCTION TO THE STUDY OF MEDICINE 

Exploeatoby Punctukes and Incisions. — Notwithstanding the 
numerous procedures of exploration above indicated, diagnosis is not 
always an easy matter. Explorative punctures and. incision are there- 
fore sometimes resorted to. 

Exploratory punctures are done by means of a syringe provided 
with a capillary needle. It is possible to thus safely draw blood, from 
a vein, cerebro-spinal fluid from the lumbar region, interstitial fluids 
from the liver and spleen, and exudates from the pleural cavity. In 
the case of muscular lesions a small punch or the harpoon of Du- 
chenne de Boulogne is employed. Finally, biopsies are sometimes 
practised — i. e., a small particle of an organ or tissue is extirpated, 
generally a little piece of skin or of tumour. All these procedures 
serve to furnish material for microscopic or bacteriological examina- 
tion. At other times puncture reveals the presence of liquid collec- 
tions. Explorative punctures are thus made into various serous 
membranes, pleura and peritoneum, as well as into organs, such as 
the liver. The punctures reveal the presence and nature of fluids. 

When puncture is inadequate, incision is resorted to. For in- 
stance, an exploratory laparotomy has for its object the exposure of 
the deep-seated organs, and, should any operable lesions be found, to 
then and there extirpate the diseased parts. 



CHAPTER XXIII 
DIAGNOSIS AND PROGNOSIS 

Questions to be solved in making a complete diagnosis — Diagnosis of infectious 
diseases — Investigation of the previous state of the subject and of the multiple 
localizations of the infectious process — Importance of clinical types — Diag- 
nosis of organic affections — Necessity of retracing the morbid series — Bearing 
of a complete diagnosis upon prognosis — Bases of prognosis — Examination of 
parts secondarily affected — Prognosis of actual manifestations — Prognosis for 
the future and for the descendants. 

When the patient has been questioned and thoroughly examined, 
having all his apparatus and organs systematically passed in review, 
a clinical conclusion should be arrived at. A diagnosis must be laid 
down — viz., the nature and causation of the present affection must 
be recognised and traced to the disease upon which it depends. 

The questions to be answered are very numerous, and of course 
vary from one case to another. They can, however, be grouped in 
the following manner : 

1. What are the present disturbances? 

2. What is their immediate cause — viz., which organ or system are 
they referable to ? 

3. Are the affected parts involved primarily or secondarily? Are 
their disorders and lesions independent or due to a common cause? 
Among the organs attacked, which one was disturbed first and to 
which are the other manifestations subordinate ? 

4. The connections of the present disturbances being disclosed, is 
it an affection or a disease that is to be dealt with? 

5. If an organic affection is present, can the disease of which it 
is a sequel be traced? 

6. What is the nature of this disease ? What position does it 
occupy in nosology? 

7. Upon what sort of constitutional ground has it evolved ? What 
will be its ulterior evolution ? 

To fix these ideas, let us first consider the infectious diseases. 

513 



514 INTRODUCTION TO THE STUDY OF MEDICINE 

In this case, after having made a complete examination of the 
patient, the physician finds himself in a position to answer the ques- 
tions raised by the diagnosis. If he can not always arrive at precise 
conclusions, he can at least closely approach a solution. In the begin- 
ning of the disease there may be some doubt, but hesitation is only 
between two or three hypotheses, and, in general, after a day or two, 
further developments lead to an exact and conclusive diagnosis. 

For example, a child or a young man is suddenly taken with a 
sore throat; there are fever, a rapid pulse, coated tongue, and a red 
throat with some whitish exudation upon the tonsils. There is ob- 
viously an acute angina. But what is the nature of this angina? To 
determine this is more difficult; the question, however, is of the 
greatest import from the standpoint of prognosis and treatment. The 
sudden onset, the pultaceous appearance of the tonsillar deposit, and 
the plainly inflammatory reaction warrant the exclusion of diph- 
theria. But, then, is it a simple or a scarlatinous angina? The age of 
the patient, the severity of the fever, the intense redness of the throat, 
the rapidity of the pulse, and at times the existence of a concomitant 
epidemic, point to scarlatina. A positive diagnosis, however, is im- 
possible before the third da} 7 , when the appearance of the eruption 
will permit a decisive conclusion. In this case a symptomatic mani- 
festation of the first importance for the diagnosis was lacking. 

In other instances a positive diagnosis can be made from the start, 
even though no sign seems to justify it. For example, a child of eight 
or ten years is suddenly attacked by intense fever; it is found dysp- 
noic, tormented with a small dry cough, its face is flushed, its cheeks 
are red, and the temperature is at 40° C. Although auscultation gives 
a negative result, pneumonia is diagnosticated, and, in fact, within 
twenty-four hours, sometimes two or three days later, the character- 
istic tubal murmur is heard. Owing to a little clinical experience, 
the diagnosis was positively made from the start, notwithstanding the 
absence of stethoscopic signs, and despite the presence, in certain 
cases of nervous phenomena or even convulsions, which would at first 
suggest meningitis. 

Illustrations could easily be multiplied. These few facts suffice to 
show that in the majority of infections a diagnosis can be laid down 
after a minute and systematic examination of the whole organism. 

Eecognition of the nature of the disease does not terminate the 
task. A man, for instance, is suddenly taken with chills, followed by 
pain in the side, painful coughing, rusty expectoration, and intense 
fever. On auscultation, a focus of crepitant rales or tubular murmur 
is found in one of the lungs. The state of the lung accounts for all 
the disturbances, and the evolution of the disease leads to the affirma- 



DIAGNOSIS AND PROGNOSIS 515 

tion that we are in the presence of an infection — i. e., pneumonia. 
All the questions requiring a solution are thus answered except the 
last one. In this instance, to make the diagnosis of pneumonia was 
not a task of difficulty; but to determine the constitutional ground 
upon which the infection runs its course is a more delicate question. 
With this object in view, the patient must be carefully questioned 
with reference to his morbid antecedents, both personal and hereditary. 
Besides, all his viscera must be attentively explored. It is something 
to have diagnosticated pneumonia by auscultating the lungs, but a 
physician should never be contented with so summary a diagnosis. 
The whole prognosis and treatment will spring from the knowledge 
he is able to acquire as to what sort of constitution the pathogenic 
agent has to deal with and as to which organs are involved. Only 
after having appreciated the previous and concomitant symptoms will 
he be able to arrive at a complete diagnosis and to predict the evo- 
lution of the disease. In case the subject is young and vigorous, 
recovery is the rule ; when an aged person is attacked, the termination 
is generally fatal. In these two instances pathology appears to fur- 
nish sufficient information. Take, for example, another patient, vig- 
orous in appearance, attacked by pneumonia. It might be thought 
that he also will recover. However, in making a systematic exami- 
nation of the organs and analysis of the urine, a lesion until then 
in a state of latency — e. g., a cardiopathy, cirrhosis, albuminuria, 
or glycosuria — is discovered. A quite different evolution is there- 
fore expected in this case, in which the situation is thoroughly 
comprehended, owing to an exhaustive, carefully conducted exami- 
nation. 

The example above given is a simple one. Furthermore, it may be 
stated that an infectious disease is diagnosticated with relative facil- 
ity. The question is one of fresh acute evolution, all the stages of 
which are followed and which has come under observation shortly 
after the onset. In most cases diagnosis can be arrived at if the 
pathology is well studied. The only point of consequence is to make 
a complete diagnosis — viz., to determine the constitutional soil upon 
which the disease is developing and the organs disturbed. In fact, 
it is known that morbid manifestations are more diffuse than was 
formerly believed. The microbic toxines affect the entire economy, 
and the task of the clinician is to make out what parts are involved 
and to what degree they are affected. It may be again stated that 
to find the name under which the disease should be designated is 
relatively easy: the mere diagnosis, however exact it may appear, 
is incomplete, inadequate, and responds only to the first, the easiest, 
and the least important part of the problem. 



516 INTRODUCTION TO THE STUDY OF MEDICINE 

With the view of facilitating the physician's task, nosologists have 
taken care to indicate a certain number of clinical forms in infections 
diseases. 

Taking typhoid fever and pneumonia as examples, it was shown 
(page 374) how, in view of either the patient's state, or of the gen- 
eral disturbances, or of the localizations, the various types could be 
classified and practical indications derived. The types, however nu- 
merous, do not, of course, respond to all clinical modes and their innu- 
merable variations; they do, nevertheless, furnish valuable elements 
of prognosis and treatment, and should therefore be very carefully 
studied. 

In certain instances the complexity of the clinical form results 
from the coexistence of various manifestations or multiple localiza- 
tions, the relations of which one to another are not easy to determine. 
- Thus, for example, in a patient suffering from erysipelas a pul- 
monary blowing murmur is perceived at a certain moment. Is it a 
case of pneumonia with streptococci — i. e., a visceral localization due 
to the agent which has caused the primary disease ? Or are we in the 
presence of an infection referable to a superadded microbe — viz., 
pneumococcus ? Both varieties of pneumonia have been observed in 
cases of erysipelas, and it is impossible to make a differential diag- 
nosis without bacteriological examination. 

The difficulty is greater when the pathogenic agents are unknown. 
In a child presenting a scarlatiniform eruption along with other in- 
fectious phenomena, how is it possible to decide whether there is 
merely a rash rather than a true scarlatina? It is right to hesitate 
even when multiple arthropathies become manifest in a scarlatinous 
patient arrived at the period of convalescence ; are they to be ascribed 
to the scarlet fever or are they dependent upon a concomitant acute 
articular rheumatism? The doubt is often inevitable in such ques- 
tions. In the absence of a positive criterion, only hypotheses can be 
put forward with regard to these morbid associations. 

The difficulties are still greater when the history of an organ 
affected is to be traced. 

Let us first consider a man suffering from intense dyspnoea, ac- 
companied with oedema of the lower extremities and pain in the right 
hypochondrium. The present symptoms are easily explained by clin- 
ical examination. In fact, fine rales are found in the lungs, albumin 
in the urine, and hypertrophy of the liver. Have the organs been 
affected independently of each other and attacked primarily? This 
hypothesis is not admissible, because, by examining each organ one 
by one, a systolic murmur is perceived at the apex of the heart, with 
irregularity in the beatings, and unequal and false steps in the pulse. 



DIAGNOSIS AND PROGNOSIS 517 

On the other hand, it is learned by questioning the patient that he 
once had an attack of acute articular rheumatism. It is then easy 
to determine the connections of the clinical phenomena. The present 
symptoms are dependent upon pulmonary, renal, and hepatic disor- 
ders, and the latter are referable to a cardiopathy — i. e., an organic 
affection which is itself nothing but a sequel of the acute articular 
rheumatism, an infectious disease. 

It should not be believed, however, that the phenomena can always 
be connected in so simple and so evident a manner. An evolution 
almost similar to the one just referred to can be discovered, the occur- 
rences having their origin in the lung. Take, for example, a man 
suffering with asthma from childhood, whose lungs have become em- 
physematous as a result of repeated dyspnoic paroxysms ; these organs 
have secondarily produced dilatation of the heart, and the cardiac 
insufficiency is responsible for the hypertrophy of the liver and the 
renal lesion with its double consequence — viz., albuminuria and 
oedema of the lower extremities. The connections of the morbid 
occurrences can only be disclosed by minute questioning and precise 
appreciation of each disturbance. 

Instead of the lungs, the kidneys may be primarily altered and 
have occasioned cardiac dilatation with all its consequences. So may 
the liver be primarily diseased and influence the other organs. 

In this manner the same parts of the organism are finally affected, 
but the course of the events varies. Prognosis is quite different from 
one case to another, and treatment can not be the same. 

Despite all the care that can be taken in examination, it is not 
always possible to trace exactly the succession of morbid occurrences ; 
in an organism in which most of the viscera are affected, the respective 
subordination of the manifestations can not be determined when their 
course and chronological appearance remain unascertained. 

Contrary to what is often stated, no particular gift, no sort of 
divinatory quality is required for classifying and interpreting the 
symptoms. The art of making a diagnosis is not inborn; it is ac- 
quired by the theoretical study of pathology and by repeated exami- 
nation of patients. It is by virtue of having observed dissimilar 
morbid states that the aptitude for correct interpretation of disturb- 
ances is formed. Indeed, clinics show us far more complex cases 
than the study of pathology leads us to suspect. The didactic trea- 
tises can give no more than schematic descriptions. They consider 
diseases in their fundamental and constant elements, disregarding 
the constitutional soil upon which they evolve. But it is owing to the 
great variability of this soil that clinical types are so numerous and 
varied, and the physician must therefore appreciate the soil upon 



518 INTRODUCTION TO THE STUDY OF MEDICINE 

which the disease or affection which he observes is developing, since 
upon that appreciation will he mostly base his judgment of the further 
evolution. 

It is often repeated that it is well to resort to the physician who 
has been your doctor for many years, for he knows your tempera- 
ment. The idea is right, but the reason is false. Long acquaintance 
is by no means necessary for the physician to appreciate the patho- 
logical value of an individual. He can appreciate it by careful ques- 
tioning and thorough examination. The age, sex, family and personal 
antecedents, and previous affections or diseases should be considered. 
Such lesions or taints which may have been left by previous patho- 
logical occurrences must next be sought for. This also is a sufficient 
reason for always submitting a patient to a thorough examination. 

When the present state, resisting power, and reactionary aptitude 
of the patient are exactly determined, and the functional energy and 
alterations of his organs are made out, then, and then only, is it pos- 
sible to predict the evolution of the morbid process under observation. 
To answer this last question is to lay down a prognosis — that is, to 
solve the most difficult and important problem in medical art. 

There are some diseases with a nearly determined evolution. In 
such cases the prognosis is derived from the diagnosis. Tubercular 
meningitis, icterus gravis, acute glanders, hydrophobia, and cancer are 
always, or nearly always, fatal. On the other hand, varicella, mumps, 
herpetic angina, and simple pneumonia in children almost invariably 
terminate in recovery. Nothing, it seems, could be simpler. Even in 
these cases, however, exceptions are met with: varicella at times 
proves fatal, and not a few distinguished physicians assert that tuber- 
cular meningitis is curable. It may be objected that these exceptions 
should not be taken into account. Leaving these facts aside, there- 
fore, let us consider a case of frequent occurrence. When in the pres- 
ence of a disease with variable prognosis, where are the elements of 
appreciation to be found? In statistics? It is theoretically known 
that pneumonia is fatal in a proportion of 10 to 20 per cent. In the 
face of a particular case, if he consults his numerical memory, the 
physician will declare that the chances of recovery are from 80 to 90 
per cent. These figures are not without interest, but what is impor- 
tant to know is whether the individual under treatment will enter 
into the 80 cases that recover or into the 20 cases that die. In this 
respect statistics are hardly of any use. They may indeed show that 
the death rate is very high for the aged and almost nil for children; 
it suffices, however, that a few of the aged recover and some of the 
children succumb in order that we be compelled to look elsewhere for 
the basis of our appreciation. 



DIAGNOSIS AND PROGNOSIS 519 

In certain instances prognosis is self-evident. There exists such an 
ensemble of symptoms as to leave no room for the slightest doubt, as 
is the case, for example, with tuberculous or cancerous patients in an 
advanced stage of cachexia, and cardiac patients at the last period of 
asystole. In such cases the only delicate point is to know how long 
life may still be prolonged. 

The greatest difficulties are experienced in those grave cases the 
termination of which must be foretold. In the first place, it should 
be borne in mind that the subjective sensations of the patient are 
often deceptive. The euphoria of cardiac, and especially of tuber- 
cular patients, even at an advanced period of the disease, is a familiar 
fact ; on the other hand, reactions of great violence may break forth 
in certain predisposed individuals and mislead to a gloomy prognosis. 
Delirium, for example, is often more alarming than grave. On the 
contrary, certain affections, although well endured, are of very serious 
prognosis. Some pleuritic patients suffer from intense dyspnoea 
from a small amount of exudation, while others breathe in an almost 
normal manner with a pleural cavity filled with fluid. The manifesta- 
tions experienced or even presented by the patient are, in fact, far 
more dependent upon his personal aptitudes than upon the state of 
the disease. They may, therefore, lead to error. 

This remark does not imply that no value is to be attached to these 
various disturbances; ground should be taken, however, not upon a 
phenomenon, but upon the ensemble of manifestations. According to 
this principle, the various clinical types have been created in nosology, 
and, although there is as yet no absolute certainty in this respect, the 
prognosis of clinical forms is already tolerably well determined by 
pathology. 

In order to arrive at more positive conclusions, greater importance 
should be attached to the state of organs or parts secondarily affected 
than to primary or principal localizations. 

There is an example which can not too often be cited — namely, 
that of pneumonia. Examination of the lung is of the greatest impor- 
tance for the diagnosis, but not so for the prognosis ; at all events, 
those parts of the pulmonary apparatus which are most important to 
consider are not precisely those occupied by the primary lesion; the 
tubal murmur is of no great consequence. An element of greater 
weight is congestion extending beyond the hepaticized zone. And 
the other organs are to be considered more than the lungs. For ex- 
ample, the heart plays the first role in pneumonia; excessive rapidity 
of its pulsations, its weakening, and the occurrence of foetal rhythm 
are of far greater consequence than the extension of the pulmonary 

process. 

34 



520 INTRODUCTION TO THE STUDY OF MEDICINE 

Analogous reflections are applicable to tuberculosis. From a diag- 
nostic standpoint the pulmonary localization possesses considerable 
importance, but is of little interest with reference to prognosis. The 
latter may be favourable even when the lesions have advanced and 
part of the apex is already excavated. The prognosis is to be deduced 
from the state of the other parts of the respiratory apparatus, and 
especially from auscultation of the bases. It will be indicated more 
particularly by accompanying phenomena — e. g., rapid emaciation, 
digestive disorders, albuminuria, and fever. These are the most sig- 
nificant manifestations. It would be easier and safer to make the 
prognosis without auscultating tuberculous subjects than to be guided 
simply by the data of stethoscopic examination. 

A last, but not least, example is furnished by cardiac pathology. 
The prognosis of an asystolic paroxysm is more safely drawn from the 
state of the other parts of the organism than from that of the heart 
itself. Why are some asystolic patients so readily re-established under 
the influence of digitalis while others are not at all benefited by the 
same drug ? The state of the heart is, of course, very important in this 
connection. The effects are entirely different according as the myo- 
cardium is or is not degenerated. At an advanced period, however, 
cardiac alterations are far from adequate to account for all. The fact 
is that the repeated attacks of asystole have given rise to cardiac 
cachexia; therefore the drug that acts upon the heart is powerless in 
an organism succumbing to consecutive alterations of other viscera — 
liver, kidneys, and lungs. 

It is evidently impossible to lay down general rules of prognosis, 
since the modifications are too considerable from one case to another. 
The few illustrations above described give a tolerably clear idea as to 
how the evolution of diseases can be predicted. Prognosis, however, is 
far from complete when it does no more than predict whether the 
individual will die or recover from the attack under observation. 
Prognosis must answer the following three questions: (1) What will 
be the termination of the present disease? (2) What is its bearing 
upon the future of the patient? (3) Of what importance is it for 
his descendants? 

It should, therefore, be determined whether the disease will be 
cured without leaving appreciable traces, and whether some disturb- 
ances will not persist in consequence. It should be decided whether 
relapses or recurrences are apt to take place, and whether they can 
possibly be guarded against. It should also be predicted whether 
there will be any sequel manifesting itself in the remote future, or 
whether the descendants of the patient will be liable to suffer from 
inherited effects of the attack; in other words, whether the disease 



DIAGNOSIS AND PROGNOSIS 521 

will for some time after its termination, or forever, expose the indi- 
vidual to the danger of begetting malformed, degenerated, or diseased 
offspring. Along with the prognosis of the individual the prognosis 
of the race must be laid down. 

Then, and then only, has the physician answered all the questions 
which incessantly meet him on confronting every patient. 

In order to arrive at a positive prognosis, ground should be taken 
upon the clinical examination of the patient, including the study of 
his antecedents, the state of his organs, and analysis of the urine. 
As to scientific procedures, they have thus far remained without im- 
portance. It was for a moment believed that bacteriology would sup- 
plant clinical observation. The study of diphtheria led to the errone- 
ous conclusion that examination of cultures permitted one to deter- 
mine the gravity of angina even in the absence of clinical observation 
of the patient. If the diphtheria was found to be uncomplicated, and 
if the bacillus developing upon the serum medium was not too long, 
the prognosis was favourable. If, on the contrary, the bacillus was 
long and mixed with numerous streptococci, the prognosis was grave. 
Although such correspondence may at times be observed, it far from 
constitutes the rule, and can not replace examination of the sick, or 
even modify the clinical prognosis made by the attending physician. 

We likewise believe that no practical information can be derived 
from inoculations into animals. Besides the difficulties of the method, 
the results are too variable to be taken as a basis of prognosis. A 
microbe virulent for man not infrequently proves inoffensive for ani- 
mals, and vice versa. Finally, Dr. M. P. Courmont has recently pro- 
posed an ingenious and interesting method of serum prognosis, but 
one which is too recent to enter immediately into practice. 

En resume, it may be said that, in the present state of medical 
science, prognosis as well as diagnosis should be based upon a thor- 
ough examination of the patient, and upon a systematic exploration 
of all his organs and apparatus. Although certain recent methods 
render great service to the physician, these are only the exceptions. 
The art of medicine can be practised by simple procedures, aided by 
the science of pathology, which requires long study, and by clinical 
experience, which can only be acquired after great and extensive 
practice. 



CHAPTER XXIV 

THERAPEUTICS 

Division of therapeutics — Symptomatic therapeutics: its usefulness — Etiological 
therapeutics; antiparasitic and antiseptic medication; bacteriotherapy — 
Pathogenic and physiologic therapeutics; mechanical procedures; antitoxic 
medication; opotherapy; serum therapy — Modifications of nutrition and of 
nervous reactions — Hygiene and prophylaxis — Vaccinations. 

The object of medicine being to relieve and cure, all our efforts 
should tend toward therapeutics. Previous studies, the examinations 
to which the patients are submitted, and investigation of symptoms, 
pathogenic or physiological processes, and etiological conditions would 
be absolutely sterile and illusory did not all these serve to favourably 
modify the morbid evolution. 

As has already been stated, therapeutics may be divided into four 
classes according to the principles upon which it is based: Symp- 
tomatic, etiological, pathogenic, and physiological therapeutics. 

Symptomatic therapeutics remedies immediate disturbances and 
combats certain disorders without reaching their cause or reascending 
to their point of departure. Although in most cases symptomatic 
therapeutics is insufficient, and is often an acknowledgment of our 
ignorance, it is at times the only possible or admissible method. In 
the presence of symptoms threatening death, recourse must be had to 
urgent treatment which is directed to the disturbance observed, with- 
out reference to its origin. When an individual is attacked by grave 
hemorrhage, it would be ridiculous to waste time in studying its eti- 
ology or pathogenesis; no matter why and how the blood flows, the 
thing 'to be done forthwith is to arrest the bleeding; symptomatic 
treatment is the only rational one. 

Likewise, when a physician is called to the side of an asphyxiated 
patient, recognised by the characters of suffocation dependent upon 
laryngeal stenosis, whatever may be the cause of the latter, his first 
thought is to re-establish the course of the air, and he immediately 
performs a tracheotomy. After this is done, there will be time to look 
522 



THERAPEUTICS 523 

for the cause, and, if possible, to act upon it — i. e., to resort to a more 
rational medication. 

Symptomatic therapeutics may serve as an auxiliary one, and is 
then perfectly justified. A patient suffering from syphilitic cephalal- 
gia must receive specific treatment. However, as the latter requires 
several days to produce its effects, symptomatic medication is at the 
same time to be resorted to in order to assuage the nocturnal exacer- 
bations of pain and procure rest to the sufferer. To this end, along 
with 4 or 6 grammes of potassium iodide directed to the syphilitic 
element, sulphonal or chloral hydrate should be prescribed to relieve 
the headache. Tuberculosis furnishes another illustration. Creosote 
and its derivatives are still the best medicines for combating this ter- 
rible infection; while administering them, however, a symptomatic 
treatment should also be made, by giving atropine for the sweats, 
opium for the cough, antipyrine for the fever, etc. 

Finally, there are cases in which, despite profound examination, 
the physician can not discover the causal disease ; he observes a symp- 
tom, and, being unable to connect it with its origin, he makes an at- 
tempt at combating it. He often succeeds in doing this and accom- 
plishes a cure. Symptomatic medication then proves to be adequate. 
Laymen constantly practise according to this method, and, for want 
of a better, physicians also resort to it by curing, for example, diar- 
rhoea by bismuth, constipation by purgatives, cough by opiates, neural- 
gia by quinine, antipyrine or phenacetine, etc. They do not know the 
cause of the diarrhoea, constipation, cough, or neuralgia; however, 
by combating the symptom, they overcome the disorder. 

Symptomatic medication thus enters the domain of rational thera- 
peutics when it remedies pressing disturbances or aids a causal medi- 
cation. It is a confession of ignorance when employed as an exclusive 
method, or is directed to combat a disorder the causation of which 
remains undiscovered. 

When we are able to trace the reactions of the organism to the 
prime cause which has called them forth, and when we can reach it, 
we employ etiological therapeutics. This mode of therapy appears at 
first to be the most rational. It would obviously seem that the sup- 
pression of the cause should result in the disappearance of all the 
consecutive disturbances. This is the application of the old adage: 
sublata causa, tollitur effectus. 

This medication, however, is often impossible, and even useless. 
It is impossible when the cause can not be reached ; it is useless when 
the cause has produced secondary disturbances evolving on their own 
account, and which may become predominant or persist alone. We 
should recall here our fundamental distinction between disease and 



524 INTRODUCTION TO THE STUDY OF MEDICINE 

affection: in disease, etiological medication is often efficacious; in 
affection, it never is. 

Thus, for instance, acute articular rheumatism is an infection 
which may be cured by a specific medication — sodium salicylate. This 
substance probably acts upon the very cause of the malady. Later on, 
when acute endocarditis is produced as a result of the acute process, 
etiological medication would be illusory : then the salicylate has noth- 
ing to do; the cardiac affection has an autonomous evolution and re- 
tains no specific character whatever from its origin. We must treat 
not the rheumatism but the cardiac affection. 

It has been stated the primordial causes of diseases are divisible 
into four groups, according as the agent is a mechanical, physical, 
chemical, or an animate one. With mechanical causes, etiological 
medication is rarely useful, since such causes have but a transitory 
action. There is only one exception — that is, when a foreign body has 
remained in a wound: to remove it is evidently etiological treatment. 

The action of physical agents is also transitory, except in the case 
of unhealthful climatic influence. To advise a patient to change the 
climate which does not suit his constitution is to practise etiological 
medication. 

There is far oftener occasion to act upon chemical causes. An 
individual swallows a poison, and it is believed that the poison has 
not yet been completely absorbed ; therefore, washing out the stomach 
with water containing, if possible, a substance capable of neutralizing 
the toxine is immediately resorted to. Thus an attempt is made at 
suppressing or at least diminishing the pathogenic action. 

The study of parasitic diseases furnishes the best examples; its 
results are the best triumphs of etiological medication. 

A child has an attack of convulsions. If symptomatic medication 
is thought to be sufficient, in this case, bromide, chloral, asafoetida, 
and the like are prescribed. The disorders will disappear only to 
reappear a few days later ; they will again be arrested under the influ- 
ence of the same treatment, but only for a short time. If, however, 
investigation being pushed further, the cause of the convulsions is 
looked for and found — for example, that the child has intestinal 
worms — a vermifuge is then administered, and the convulsions dis- 
appear in a definite manner. 

Removal of the Medina worm, ablation of an Ixydatid cyst, the use 
of germicidal or antiseptic salves or solutions are as many examples of 
etiological medication. 

It is to be noted, however, that in many cases the procedure re- 
sorted to is highly complex. When, for example, oidian stomatitis is 
treated by means of bicarbonate or borate of sodium, the medication 



THERAPEUTICS 525 

is not, as was once believed, etiological, since the parasite of aphtha 
thrives perfectly in an alkaline medium. The substances employed 
exert an indirect influence — they improve the state of the mucous 
membrane, and thus favour the destruction of the vegetable. 

When an infectious agent is to be combated, etiological medica- 
tion can be applied by means of antiseptics. The method succeeds 
when it is desired to disinfect a surface or an easily accessible cavity. 
Its application is more difficult when deep-seated cavities are to be 
treated. It can, however, be employed either by means of inhalations 
of antiseptic vapours, in the case of the respiratory passages, or by 
the ingestion of insoluble substances in the case of the digestive canal. 
The use of menthol inhalations in the former instance, and that of 
naphthol, benzonaphthol, betol, or salol in the latter, renders real serv- 
ice. Several authors believe that it is possible to go farther and con- 
tend that various substances, especially tannin, are capable of render- 
ing the internal medium antiseptic. 

Possibly, though not certainly, the so-called specific medications 
are of an etiological order. Mercury or potassium iodide given in 
syphilis, quinine in malaria, sodium salicylate in rheumatism, and 
potassium iodide in actinomycosis perhaps exercise a destructive 
action upon the known or unknown agents of these diseases. It may 
just as well be argued, however, that these medicines exert their effect 
upon the organic cells by increasing their resistance. 

The desire of reaching the animate cause of infectious diseases 
has given rise to many methods. Besides antiseptic and specific medi- 
cations there is bacteriotherapy, which consists in combating a patho- 
genic microbe with an inoffensive one. For instance, inhalation of 
Bacterium termo cultures are prescribed for consumptives. The results 
have not, however, been encouraging. The soluble products have then 
been resorted to. It was long ago noticed that an intercurrent ery- 
sipelas could improve a cutaneous tuberculosis. Hence the attempts 
at treating lupus by means of sterilized cultures of streptococcus, the 
action of which was re-enforced by the addition of a few drops of an 
equally sterilized culture of Bacillus prodigiosus. In some instances 
improvement has been obtained; the dangers, however, to which the 
use of microbic products exposes the patients do not seem to be com- 
pensated by the results. It has not been demonstrated that the 
effects of this toxibacteriotherapy are due to action upon the specific 
bacillus; it is even more probable that there is simply stimulation of 
the reactional activity of the organism. 

Anticancerous bacteriotherapy is doubtless to be understood in the 
same manner. The injection of living cultures or of a mixture of the 
toxines of streptococcus and of Bacillus prodigiosus (Coley's method), 



526 INTRODUCTION TO THE STUDY OF MEDICINE 

has afforded some interesting results, especially in the treatment of 
sarcoma. 

The method is likewise etiological when germicidal serums are em- 
ployed. This is a variety of antiseptic treatment, since a substance 
is introduced which is highly toxic for the microbes, very slightly so 
for the individual. 

Finally, certain abortive treatments are to be included in the 
group of etiological medications. 

Abortive medication may aim at three ends : to arrest a disease 
while yet in its prodromic stage, to prevent a disease from passing 
from one stage to another, and to cut short a morbid evolution. 

In the case of gonorrhoea is found an example of abortive medica- 
tion employed at the prodromic period. At the moment when a slight 
discharge of mucus begins, while the gonococcus is still in the super- 
ficial parts, the injection of a somewhat strong antiseptic may de- 
stroy the pathogenic agent. The method is abortive when the uterus 
is curetted in the beginning of puerperal fever; the cause of the dis- 
ease is thus acted upon, since the uterine mucous membrane is, so 
far as is possible, freed from the streptococci invading it. 

In the examples just chosen medication was of an etiological 
order. When abortive treatment is applied to a disease which has 
already been evolving for a more or less long period, the procedures 
employed are more complex. The cause is then less easily accessible 
and the action of therapeutic measures is brought to bear rather 
upon the diseased organism. This is pathogenic or physiological 
medication. 

Pathogenic medication derives its guidance from the mode of action 
of the causes. The latter may act in two different ways : mechanically 
or chemically. They give rise to two forms of reactions — namely, 
nervous reactions and nutritional disturbances — the study of which 
constitutes pathological physiology. To these four modes of action 
and reaction correspond four therapeutic methods. 

To mechanical causes are generally opposed mechanical treatments. 
In case of traumatism, simple mechanical procedures are employed 
to assure hemostasis, extraction of foreign bodies, coaptation of sepa- 
rated parts, and the maintenance of fractures. When the mechanical 
causes are of an internal order, the principles are the same. In cases 
of pleural, pericardial, or abdominal effusions compressing the sub- 
jacent organs and embarrassing their function, the indications are 
quite plain — namely, evacuation of the fluids. Likewise, in case of a 
strangulated hernia, intestinal occlusion, or obstruction of the bile 
duct, the physician endeavours, by mechanical means and surgical 
intervention, to stop the compression and suppress or remove the 



THERAPEUTICS 527 

obstacle. Mechanical procedures are also resorted to in cases of dis- 
placement of organs, hernia, eventration, and ptosis. 

The procedures are often difficult of realization; intervention 
may be extremely delicate, but the indications are very simple. 

Of the causes acting chemically, toxines are the most important. 

In treating an individual who has swallowed a poison, the first 
indication is to wash out the stomach, thus removing along with the 
yet unabsorbed part of the toxine a certain amount of the same 
already eliminated by the gastric mucous membrane. In view of this 
fact lavage may be resorted to even when the poison has been intro- 
duced subcutaneously, as is often the case in morphine poisoning. At 
the same time physiological medication must be employed, which con- 
sists in favouring elimination through the various emunctories : pur- 
gatives, enemata, and diaphoretics are prescribed. Renal secretion 
particularly must be encouraged by the use of copious diuretic and 
hot beverages, and by subcutaneous or intravenous injections of salt 
water, with or without bloodletting. It is well to note that of these 
means some have a complex action. For instance, bloodletting does 
not act merely as a means of removing the poisons accumulated in the 
blood; it also modifies the phenomena of absorption and excretion by 
diminishing the blood mass. If the poison is not yet completely 
absorbed, bloodletting may hasten its penetration, and thus prove 
extremely harmful. We say " may," since this opinion is based upon 
an old experiment of Magendie. This author noticed that bloodlet- 
ting favoured the toxic action of nux vomica introduced into the 
stomach; he thought that penetration into the blood was facilitated 
by the fact that the organism drew water to replace the loss of blood. 
The conclusion is acceptable, but, in order to be fixed, it requires new 
investigations, as the experiment is indeed highly complex. 

In cases of auto-intoxication bloodletting can be resorted to with- 
out hesitation. It is daily practised with success upon ursemic pa- 
tients. It serves to throw out with the blood a certain amount of the 
circulating poison, and, at the same time, through the osmotic current 
which it establishes from the tissues toward the blood, to prevent the 
accumulation of toxines in the tissues. 

If it is feared that bloodletting will weaken the patient and, by 
reducing the blood mass, diminish the renal secretion, injections of 
artificial serum should at the same time be resorted to. The latter 
act by favouring the elimination of crystalloid substances, which pass 
more easily through the kidneys, and especially by stimulating the 
nervous system, the dynamogenic power of which is increased. This 
form of medication is therefore a complex one, and it effects more 
than a simple washing of the organism. 



528 INTRODUCTION TO THE STUDY OF MEDICINE 

Neutralization of toxic substances may also be aimed at. This is 
very readily done when the poison is ingested. If it is an acid, then 
some alkaline solution, preferably a water charged with calcium or 
magnesium salts, is introduced into the stomach; there is some 
chance of thus forming insoluble combinations. If the ingested 
poison is exactly known, the medication can more readily be formu- 
lated. A substance capable of precipitating the toxine must be em- 
ployed; the calcium salts, for instance, in case of oxalic or sulphuric 
acid; sodium chloride in case of silver salts; and tannin in alkaloidal 
poisonings. We shall not dwell upon these indications furnished by 
the study of elementary chemistry. 

In order to relieve the pain and thirst of the patient, milk is 
often prescribed, this liquid possessing the additional advantage of 
being a diuretic. It is well, however, to remember that the use of milk 
may produce harmful effects; when the patient has swallowed a poi- 
son which is soluble in a fatty substance, as is phosphorus, milk 
hastens the development of disturbances; it should therefore be for- 
bidden, and substances which favour oxidation should be prescribed, 
such as turpentine. 

Neutralization of the poison is possible even when it is introduced 
subcutaneously. The action of venoms is very often arrested by means 
of various substances, such as potassium permanganate and hypo- 
chlorites. 

If the poison has been absorbed and has penetrated into the or- 
ganism, can its effects be neutralized ? This is believed to be possible 
by means of antidotes. 

The antidote, such as was conceived by old authorities and as is 
still understood by several at the present day, does not exist. To be 
real antidotes, the substances should mutually neutralize the effects 
of each other, or, in other words, exert upon the organism influences 
diametrically opposed. The fact is, however, that between poisons 
there exist only partial antagonisms or influences which can be neu- 
tralized by a complex mechanism. It is stated, for instance, that 
atropine and morphine are two antagonistic substances; it is true 
that they have contrary effects upon different apparatus. Yet one is 
not the antidote of the other, since death is produced far more rapidly 
by injecting a mixture of the two poisons than by the injection of but 
one of them. Atropine is also said to be the antidote of muscarine. 
Atropine paralyzes the extremities of the pneumogastrie nerves and 
suppresses the inhibitory action of these nerves upon the heart. Mus- 
carine arrests the heart by acting upon the pneumogastrie; it will 
therefore have no influence upon an atropinized animal. But this is 
a case of physiological antagonism and in no wise one of antidotism. 



THERAPEUTICS 529 

Therapeutic serums are at times considered as antidotes: the 
antidiphtheritic serum is said to neutralize the diphtheritic poison 
as an acid neutralizes a base. Such was Behring's view, but it is not 
correct. The serum acts, not by destroying the poison, but by in- 
creasing the resistance of the organism. Serum therapy is not an 
antidotal but a pathogenic and physiological medication. 

What is now generally designated as opotherapy (organotherapy) 
may perhaps be considered to be for the most part antidotal. It is 
well known in what it consists. When an organ is altered or sup- 
pressed, the patient is given the extracts prepared from the same 
organs taken from animals. Brown-Sequard, who initiated this thera- 
peutic method, prescribed subcutaneous injections of testicular juice ; 
he thus supplied the organism with the internal secretion which the 
testicles seem to elaborate for the stimulation of the nervous system. 
At the present day the thyroid gland is mostly used, which, when in- 
gested or injected beneath the skin, effects marvelous results in myx- 
edema and in certain cases of obesity. Some encouraging results 
have been observed with the extract of liver in ovariotomized women. 

Although antidotal medication in the old sense is no longer admis- 
sible, it is not impossible to favour the destruction and transforma- 
tion of poisons. Certain medicines transform toxines into harmless 
substances; others exert an indirect influence by stimulating the 
activity of organs which are capable of annihilating or, we could 
almost say, digesting the poisons. Special therapeutic effort should 
be devoted to the liver, for it is demonstrated that the ingestion of 
sugar or of small doses of ether constitutes an excellent means of 
stimulating this organ and* of increasing its action upon poisons, and 
its destructive power upon microbes. Finally, along with substances 
neutralizing toxines should be placed those which, by rendering them 
more soluble and dialyzable, favour their excretion. This method is 
most frequently applied to the treatment of auto-intoxication, and it 
is realized by the use of oxidants. 

It has several times been stated that when the disease appears to 
be terminated, and the poison which gave rise to it is eliminated, the 
organism is not completely restored to its normal state. The persist- 
ing disturbances may be too slight to demand attention, while in other 
cases they may be evidenced by a series of nutritional modifications 
which are always consecutive to toxic, exogenous, autogenous, or in- 
fectious influences, and may be transmitted by heredity. 

The disorders of nutrition are divisible into two types, according 
as the exchanges are accelerated or diminished. In the former case 
the nutritive process should be moderated, as is realized by means of 
so-called sparing (or economizing) medicines, such as arsenic and 



530 INTRODUCTION TO THE STUDY OF MEDICINE 

valerian. In the latter case the nutritive movement should be stimu- 
lated ; to this effect the salts of Carlsbad, Vichy water before meals, or 
potassium iodide in small doses, 20 centigrammes daily, are prescribed, 
along with cutaneous stimulations, douches, massage, and dry fric- 
tions; finally, the elimination of incompletely oxidized or poorly sol- 
uble substances should be facilitated by the administration of lithine 
and piperazine, which dissolve uric acid, and by sodium benzoate, 
which favours oxidation. 

Of these various therapeutic procedures, several act upon nutrition 
indirectly, by modifying nervous reactions. 

Nervous reactions, as we have already shown, play a role of com- 
manding importance in pathology; their intervention is to be con- 
sidered in local lesions and in general disturbances. 

When a local reaction is produced, the physician may propose to 
exaggerate the functional derangement, to combat it, and cause its 
disappearance by derivation. 

Medication which aims at exaggerating the functional disorder is 
called naturistic, and is frequently employed. Suppose, for instance, 
a case of acute peritonitis. The individual suffering from it is con- 
stipated; our treatment may consist in prescribing opium to increase 
the constipation, since this disorder serves to immobilize the intes- 
tine, and thus to prevent the extension of the inflammatory pro- 
cess. On the other hand, a purgative medicine is not infrequently 
prescribed for a patient attacked by diarrhoea, for the reason that the 
intestinal fluxion carries out microbes and toxines, and by exaggerat- 
ing this fluxion we render the purification complete. For the same 
reason an emetic is administered in case of an attack of indigestion 
with nausea, and kermes, or white oxide of antimony, is given to 
favour expectoration. This method of therapeutics derives all its 
guidance from the reactions produced; it completes the work under- 
taken by Nature. 

In certain instances therapeutics endeavours to recall disturbances 
which have subsided, and to awaken natural reactions which have 
become dormant. When a lesion has lasted for a certain length of 
time the process of repair may stop; the curative inflammation is 
not then sufficiently marked, and therefore the reaction needs to be 
stimulated. This is accomplished by the employment of heat, by 
scarifications, and by cauterizations with silver nitrate, zinc chloride, 
etc. In this manner the physician resumes the task undertaken and 
left incomplete by Nature. Tuberculin also belongs to this order 
of medication. This substance, as is known, represents an extract 
of cultures and the protoplasm of Koch's tubercle bacillus. Its intro- t 
duction into a tuberculous organism gives rise to local and general 



THERAPEUTICS 531 

reactions which, although often very serious, may sometimes promote 
repair by the stimulation thus produced. 

It should not, however, be assumed that naturistic indications are 
always to be followed; in many cases reactions are too intense, dis- 
orderly, and undisciplined, so to say, and the physician's duty is then 
to resort to antinaturist therapeutics. Too intense congestions and 
inflammations, too energetic spasmodic reactions must be combated 
by means of revulsives, refrigerants, and calming measures. 

Finally, in case of very troublesome or dangerous manifestations, 
relief may be sought by means of revulsion or substitution. The old 
physicians often had recourse to these procedures : moxas as well as 
setons have rendered real service ; dry or scarified cupping, sinapisms, 
cauterization, faradization, and hot or cold applications are still daily 
employed. And, though setons are out of fashion, the abscesses of 
fixation, such as are recommended by Dr. Fochier, amount almost to 
the same thing; it is a procedure rejuvenated and explained by new 
pathogenic views. 

For disturbances resulting from congenital or acquired morbid 
aptitudes of the nervous system there are two orders of medi- 
cations. 

When reactions are too intense and irregular, sedative therapeu- 
tics should be resorted to. Materia medica furnishes some very serv- 
iceable medicines, such as the bromides, valerian, and asafcetida. The 
best results, however, are obtained by modifying the hygiene and 
mode of life of the patients. Neuropaths must lead an existence 
free of anxiety and dissipation. It is to be borne in mind that sorrow 
is in many cases the occasional cause provoking the development of a 
neurosis until then in a state of latency, such as hysteria, epilepsy, or 
mental derangements, and that the first inebriety is the starting point 
of dipsomania. Moreover, according to the patient's temperament — 
and here the physician requires perfect tact — he should be advised to 
travel, to live in the country or at great altitudes, or, on the contrary, 
to enjoy worldly distractions. Psychical treatment affords the best 
results in such cases. The physician must enjoy in the esteem of the 
patient an authority so high as to inspire him with his will, even, if 
needed, through suggestion. It is also to be remembered that neurop- 
athies are hereditary. Although they may be exaggerated in the 
descendants to the point of appearing to be spontaneous, they already 
existed in the parents. In many cases the disorders are kept up 
by associates of the patient; under such circumstances life far 
from the family circle may produce marvellous results and lead to 
recovery. Physical procedures should be conjointly employed — e.g., 
progressive and rhythmical exercises, gymnastics, and, on the other 



532 INTRODUCTION TO THE STUDY OF MEDICINE 

hand, massage, bathing, and douches, which are rightly too popular 
to need further commendation here. 

When, on the other hand, the nervous system of a patient is in- 
capable of adequately reacting, recourse is to be had to stimulations, 
massage, hydrotherapy, and cutaneous frictions, which act in this 
as in the preceding case by regulating nervous activity. At the same 
time various medicines should be prescribed, among which strychnine 
sulphate, in doses of 2 milligrammes daily, is the one most employed. 

Finally, there is also a method calculated to impress the nervous 
system with a profound modification. This is designated as pertur- 
bating therapeutics, such as was commended by Trousseau. It con- 
sisted in stimulating the nervous system by large doses of active 
medicaments. In cases of chorea, for instance, strychnine was admin- 
istered until convulsions appeared, and the nervous perturbation thus 
produced resulted in the disappearance of the choreic symptoms. The 
procedure is at present abandoned, but the method remains : the use 
of ice-water baths in certain grave diseases of the nerves represents a 
real perturbating medication. 

Hygiene and Prophylaxis. — Although it is well to treat patients, 
it is better to give rules for avoiding disease. This last part of 
medicine, hygiene and prophylaxis, has to-day acquired a legitimate 
importance. Since the cause of infectious diseases is known and 
the mystery of their transmission penetrated, and since the relation- 
ship between human and animal pathology is comprehended, and pre- 
cise views have been arrived at as to the necessity of disinfection and 
quarantine, sanitary measures have been adopted which have pro- 
duced wonderful results. The extension of diseases has been pre- 
vented, epidemics have been arrested, and the number of infections 
reduced. The introduction of hygiene into schools, barracks, and fac- 
tories has lowered morbidity and death rate in notable proportions. 

Furthermore, the use of vaccination tends to cause a certain num- 
ber of infectious diseases to disappear. 

Vaccination. — Vaccination consists in introducing into an organ- 
ism an active virus, attenuated or inoffensive, living or sterilized, in 
such a manner as to create a state of immunity against this virus or 
against another one. 

The first attempts date from antiquity. The practice of varioliza- 
tion appears to have originated in China three thousand years ago. 
It spread to Persia, and then, in 1673, was introduced into Turkey 
by E. Timoni and J. Pylarini. In 1721, Lady Montague, who had 
seen its results in Constantinople, made the method known in 
England. 

If a trace of variolous virus is inoculated into a healthy individ- 



THERAPEUTICS 533 

ual, a discrete, benign variola develops, conferring immunity upon him 
against the dangers of spontaneous smallpox. The innocuity of the 
inoculated variola is due to the fact that it is deposited in a tissue 
slightly favourable to its development, and that it is introduced into 
a resistant organism eapable of overcoming morbid germs. The 
gravity of spontaneous smallpox depends, on the contrary, upon the 
predisposition of the subject who has permitted the development 
of the malady. 

Nevertheless, variolation exposes to dangers. The resulting dis- 
ease is quite often serious, and, at all events, it may be transmitted 
to those about the patient and become the starting point of an epi- 
demic. 

The method therefore is but of historical interest, at least with 
reference to the human species, for the active viruses of rot, of symp- 
tomatic anthrax, and of cattle pneumonia are inoculated into animals 
in a region in which the cellular tissue is dense and therefore not 
very favourable to the development of the infection — such, for exam- 
ple, as the tail. 

There is another procedure which consists in inoculation of an 
inoffensive, or nearly inoffensive, virus to protect against another 
virus. Such is the principle of Jennerian vaccination. 

It was long known in certain regions of England, and especially 
in the county of Gloucester, that individuals taking care of cows often 
presented upon their fingers small pustules contracted by contact 
with cattle affected with cowpox, and that such eruption rendered 
them immune to smallpox. In 1768, Sutton and Fewster drew atten- 
tion to these facts. It was then that Jenner conceived the idea of 
practising in a systematic manner and with a prophylactic view the 
inoculation of cowpox. In 1798 he published the results of his re- 
searches; he established the inoculation of the cowpox from the cow 
to man, its transmission from man to man, and proved that immu- 
nization is surely conferred by inoculation of the vaccine. 

The inoculation of humanized virus (Jennerian vaccine, properly 
so called) was preferred for a long period, but at present the animal 
virus is again resumed, taken directly from a vacciniferous calf or pre- 
served in the form of glycerinized pulp. 

It is hardly necessary to recall here the results obtained by means 
of vaccination, which, were it practised in a regular manner, would 
cause one of the greatest scourges of humanity to disappear forever. 
It is not worth while to discuss the practical side. The theory is less 
certain. Most authorities are of the opinion of Chauveau, that vac- 
cinia and variola represent two distinct diseases. It has been objected 
to this view that we know of no infection immunizing against a differ- 



534 INTRODUCTION TO THE STUDY OF MEDICINE 

ent infection. It is true that the microbe of chicken cholera and the 
streptococcus impart a certain degree of immunity against anthrax, 
but the resistance thus produced is not constant, and, at all events, is 
quite weak. Hence, taking ground upon clinical analogies and some 
experimental researches which are, however, under dispute, some au- 
thorities have asserted that vaccinia is nothing more or less than 
a modified smallpox. The conception is by no means illogical, since 
a certain number of pathogenic agents are known to be liable to such 
profound modifications. If the demonstration be some day rendered 
conclusive, Jennerian vaccination will then be considered as the first 
example of the inoculation of an attenuated virus, and it would enter 
into another method to be presently referred to. 

In fact, instead of introducing active viruses, we may utilize atten- 
uated — i. e., accidentally or experimentally modified — agents. Such 
is the principle of Pasteurian vaccinations. 

Attenuation can be eifected in a great number of procedures. 
Most of these consist in causing the agent to grow under dysgenetic 
conditions, or in disturbing its vitality by physical or chemical means. 
Letting the cultures grow old, submitting them to heat, exposing 
them to the sun, developing them at high temperatures, the addition 
of antiseptic substances to the medium, the influence of compressed 
oxygen — such are the most usual procedures. In addition to these, 
there are also the serial inoculations in certain animals : the virus 
becomes more powerful for the species experimented upon; at times 
it becomes weaker for another species, a result which may be regarded 
favourable to the original unity of smallpox and of vaccinia. 

Be that as it may, the Pasteurian vaccinations are employed espe- 
cially in veterinary medicine, and afford remarkable results against 
anthrax. Pasteur's method consists in the inoculation of two vac- 
cines : the first, the weaker one, proceeds from a microbe which has 
remained in a temperature of 42° C. from fifteen to twenty days. 
From 1882 to 1894, 1,788,677 sheep were vaccinated in France; 
their death rate has been 0.94 per cent, while previously it was 10 
per cent. With cattle, the death rate has fallen from 5 to 0.34 
per cent. 

In view of these facts, it has been a question whether vaccines 
would not act even after the introduction of an active virus. It was 
also Pasteur who took up and solved this new problem. The hydro- 
phobic marrow, weakened by desiccation, is injected into individuals 
bitten by a rabid animal. In this manner it is possible to create a re- 
fractory state, which is more rapidly developed than the disease. Im- 
munity manifests itself early enough to prevent the propagation of 
the active virus and to enable the organism to destroy it. 



THERAPEUTICS 535 

It has already several times been stated that the pathogenic agent 
acts only by the soluble products which it produces. This law is 
equally true of vaccination, as is demonstrated by numerous experi- 
ments, the first of which are due to Salmon and Smith. Sterilized 
cultures can therefore be substituted for the attenuated viruses ; they 
have not, however yet been utilized in practice : there have been but 
a few attempts made with a view of guarding against cholera. 

The preventive injection of a therapeutic serum is sometimes con- 
sidered as a vaccination. In time of epidemic the antidiphtheritic 
serum has often been administered; the antitetanic serum is em- 
ployed in wounded individuals. Thus is conferred an immunity which, 
unluckily, is not a lasting one. Serum therapy has not at all the 
same action as vaccination: it impregnates the organism with sub- 
stances which are not very favourable to the development of the 
pathogenic agent (germicide serums), or with substances which in- 
crease the resistance of the cells against toxines (antitoxic serums). 
The economy becomes impregnated without reacting, and the immunity 
rapidly disappears as the foreign serum is eliminated : this is what is 
termed passive immunity. Vaccination, on the contrary, creates an 
active immunity; it does not introduce any germicide or antitoxic 
substance, but it stimulates organic reactions which result in the pro- 
duction of protective matters. Immunity in this case is the work of 
the vaccinated individual; his entire nutrition is modified for a more 
or less considerable period, and hence resistance is durable. 

We have dwelt upon the history of vaccination because this 
method is one of the most admirable discoveries of modern times. 

Owing to Jenner's genius, one of the most fearful diseases of 
the human race has almost entirely disappeared. Smallpox has be- 
come a disease of such rare occurrence that certain German authori- 
ties believe it is no longer observable in countries truly civilized; 
it will ere long become an infection of merely historical interest. 
Thanks to Pasteur's genius, anthrax diseases are disappearing in their 
turn; hydrophobia is becoming exceptional, and it is perhaps per- 
missible to expect the day when tuberculosis itself will be overcome. 
Finally, although the mechanism is different, the serums drawn from 
vaccinated animals also constitute a preventive method of impor- 
tance; their injection appears to be capable of preventing the devel- 
opment of diphtheria, tetanus, plague, and certain septicaemias, espe- 
cially puerperal fever. 

We can therefore perceive in the remote future the day when 

prophylaxis will have completely replaced medicine. It must be 

acknowledged, however, that for a long period of time there will yet 

be patients to be treated. Whenever possible, etiological medication 
35 



536 INTRODUCTION TO THE STUDY OF MEDICINE 

must be resorted to. When the cause is inaccessible, the methods 
based upon pathogenesis and pathological physiology are to be em- 
ployed. Finally, in a great many cases, symptomatic medication has 
to be made use of, no other being possible. At times even empiricism 
must be utilized. 

Empiricism is not, as is often stated, the negation of science; it 
represents the first stage of science. It is an unreasoned (not unrea- 
sonable) experiment transmitted to us by tradition. It is known that 
such a medicament cures, although its mode of action is not under- 
stood. It is therefore right to make use of it, at the same time en- 
deavouring to make a complete study of it. With the advance of 
science empirical notions will disappear, yielding their place to scien- 
tific therapeutics. 

To be able to formulate rational medication many years must be 
spent in studying the mode of action of causes and the reactions of 
the organism. It is only after having made a complete theoretical 
study and become thoroughly familiar with modern acquisitions in 
etiology, pathogenesis, and physiological pathology that one can 
undertake medical practice. The science is the basis of the art, and 
therefore its teachings, even though abstract in appearance and at 
times of a purely speculative interest, are indispensable for the prac- 
tice of medicine. Still, the study of special pathology, however impor- 
tant, is inadequate; before and after it, alongside of and above it, is 
seated general pathology, which alone can guide the physician in his 
career; it only can furnish the directing ideas which will conduct 
him to a reasoned and therefore effective therapeutics. 



METRIC TABLES 



Table for reducing the Metric System into the English {Troy Weights) 



Grains to Grammes. 



¥00 

1 
195 

1 

TFo 

1 

185 

I 
180 

1 
175 

1 

TTo 

1 
T65" 

1 . 
160 

1 
155 

1__ 
150 

1 
145 

L_ 

140 — 

_1 

1 33" — 
_]_ 

130 — 

1 

T25 — 

1 

120 — 

1 

TTT — 

1 

TT — 



= 0.00033 
= 0.00034 
= 0.00035 
r 0.000357 
= 0.00036 
= 0.000377 
= 0.000388 
= 0.0004 
= 0.000413 
= 0.000425 
= 0.00044 
-.0.000455 
= 0.00048 
= 0.00049 
= 0.0005 
0.000528 
0.00055 
0.000574 
0.0006 



Grains to Grammes. 



100 — w 





1 

9 5" 



7^0=0 

-6 J O=0 

55 

5V = 

45 









4^ = 
3 1 0=0 

/o=0 



000628 

00066 

00694 

0073 

0077 

0082 

0085 

0094 

001 

0011 

0012 

00132 

00146 

00165 

00188 

0022 

00264 

0033 

0044 



Grains to Milligrammes. 

1= 64.8 

2 = 120.6 

3 = 194.4 

4 = 259.2 

5 = 324 

6 = 388.8 

7 = 453.6 

8 = 518.4 

9 = 583.2 
10 = 648 

1 drachm or 60 = 3 . 89 grammes. 
1 ounce or 480= 31.1 



Grains to Grammes. 



tV = 0, 



* = o 



5=0 

i = o 

i = o 



1 = 0, 

2 = 0, 

3 = 

4 = 

5 = 

6 = 

7 = 

8 = 

9 = 
10 = 



0055 

0066 

0082 

0094 

011 

0132 

0165 

022 

033 

066 

132 

198 

264 

33 

396 

462 

528 

594 

66 



Grammes to Grains. 



1 = 

2 = 

3 = 

4 = 

5 = 

6 = 

7 = 



15.43 
30.86 
46.29 
61.72 

77.15 

92.58 

108.01 



8 = 123.44 

9 = 138.87 
10 = 154.3 



Metrical Measures of Length 



Millimetre 
Centimetre 

Metre 

Kilometre 



In English inches. 



0.03937 

0.39371 

39.37079 

39370.79000 



In English feet 
= 32 inches. 



0.003281 

0.032809 

3.280899 

3280.892200 



In English yards 
= 3 feet. 



0.0010936 

0.0109363 

1.0936331 

1093.6331000 



In English miles 
=1760 yards. 



0.0000006 
0.0000062 
0.0006214 
0.6213824 



1 inch = 2.539954 centimetres. 

1 foot = 3.0479449 decimetres (decimetre is one tenth of a metre). 

1 yard = 0.9143835 metre. 

1 mile = 1.6093149 kilometre. 

537 



538 INTRODUCTION TO THE STUDY OF MEDICINE 



Formulae for the Conversion of Degrees of Fahrenheit' 's Thermometer 
into those of Centigrade, and vice versa 

F. = Fahrenheit. C. = Centigrade. D. = Degree observed. 

If above the freezing point of water (32° F., 0° C.) : 
F. into C. (D. - 32) -*- 9 x 5. (For example, 104° F. = 104 - 32 -5- 9 x 5 = 40° C.) 
C. intoF. D. --5x9 + 32. (For example, 37° C. = 37-*- 5 x 9 + 32 = 98. C° F.) 

If below the freezing point of water, but above 0° F. : 
F. into C. - (32 - D.) ~- 9 x 5. (For example, 14° F. = (32 - 14) h- 9 x 5 = 

- 10° C.) 

C. into F. 32 - (D. -f- 5 x 9). (For example, - 16° C. = 16 -f- 5 x 9 = 28.8 and 
32 -28.8 = 3.2° C.) 
If below 0° F. : 
F. into C. - (D. + 32) -j- 9 x 5. (For example, - 22° F. = 22 + 32 -s- 9 x 5 = 

- 30° C.) 

C. into F. - (D. -f- 5 x 9) - 32. (For example, - 20° C. = 20 -*- 5 x 9 - 32 = 

- 4° F.) 



INDEX 



Abasia, 465. 

Abdomen, deformities of the, 409. 

Abscesses, 265 ; in visceral pyaemias, 293. 

Achromatopsia, 478. 

Acromegalia, 409. 

Actinomycosis, 113. 

Addison's disease, 412. 

Adenoma, 308. 

Adenopathies, 414. 

Affection, distinction of, from disease, 6. 

Age, r6le of, in the contraction of in- 
fectious diseases, 140; in variations of 
nervous reactions, 175; in nutrition, 
190; in the development of tumours, 
311. 

Agents, mechanical, 13-33; physical, 34- 
60; chemical, 61-80; animate, 81-132; 
infectious, 98; specific and nonspecific 
infectious, 86; classification of infec- 
tious, 116-118. 

Agraphia, 490. 

Air, action of compressed, 40; poisons of 
the, 69; microbes of the, 122. 

Albumin, test for, 503. 

Albuminuria, passage of toxines through 
the kidneys, cause of, 130. 

Alcoholism, 64. 

Alexia, 489; musical, 490. 

Altitude, action of, on the organism, 37; 
cure, 39. 

Amblyopia, 477. 

Amimia, 489. 

Amoeba, of dysentery, 115. 

Amusia, 490. 

Amyotrophia, 482. 

Anaphrodisia, in diabetics, 460. 

Anatomy, pathological, 1, 9. 

Anginas, differential diagnosis of, 442. 

Angioma, 308. 



Anthrax, bacillus of, 106; poisons of, 166. 

Antidote, 528. 

Antisepsis, 525. 

Anuria, 456. 

Aphasia, 489, 490. 

Aphemia, 490. 

Appendicitis, 103. 

Apraxia, 489. 

Arteriosclerosis, 301; evolution of clin- 
ical forms of, 303 ; therapeutics of, 304. 

Arthritism, 194. 

Ascarides lumbricoides, 95. 

Asphyxia, 411. 

Astasia-abasia, 465. 

Asthenopia, 474. 

Ataxia, 465. 

Athrepsia, ,189. 

Aura, 471. 

Auscultation of the heart, 418; of the 
lungs, 434; of the stomach, 449. 

Auto-intoxication, 185; normal, 196; 
pathological, 201; secondary, 356. 

Bacillus, 89; specific, 106; of soft chan- 
cre, 111; of symptomatic anthrax, 112; 
of cholera, 113; colon, 103; of diph- 
theria, 107; Eberth's, 107; of gaseous 
gangrene, 111; of glanders, 106; of in- 
fluenza, 109; Koch's, 109; of leprosy, 
110; Loeffler's, 107; of psittacosis, 104; 
pyogenes fcetidus, 104; of plague, 110; 
of rheumatism, 112; of septicus puti- 
dus, 104; of tetanus, 111; of tubercu- 
losis, 109; of typhoid, 107; of yellow 
fever, 110. 

Bacteria, 86 ; division of, 88 ; varieties of, 
89 ; schematic aspect of the species of, 
88; action of the sun upon, 120; ac- 
tion of, upon each other, 143-147; 

539 



540 



INTRODUCTION TO THE STUDY OF MEDICINE 



microscopic examination of, 508; cul- 
tivation of, 509. 

Bacteriaemia, 285; auto-, 288. 

Bacteriotherapy, 525. 

Bacterio-toxsemia, 2S5. 

Bile, toxicity of, 201 ; test for, 502. 

Bladder, examination of the, 459. 

Blood, modifications of, in altitudes, 38; 
role of, in infections, 150, 169, 285-294; 
clinical examination of, 504; micro- 
scopic examination of, 505-507. 

Bloodletting, 527. 

Braidism, 53. 

Burns, 42. 

Cachexia, cardiac, 335. 

Calorimetry, 496. 

Camptodactylia, 409. 

Cancer, parasitic theory of, 314. 

Catalepsy, 53, 485. 

Cathodic rays, 495. 

Causes, efficient, auxiliary, and predis- 
posing, 6; occasional, intervention of, 
in inherited nervous disorders, 232. 

Caustics, 61. 

Chancre, soft, bacillus of, 111. 

Chest, deformities of the, 408, 431; ex- 
amination of the, 431. 

Cheyne-Stokes respiration, 430. 

Chlorosis, 190, 410. 

Cholera, bacillus of, 113; poison of, 165; 
facies, 407; nostras, 103; infantile, 
103. 

Chondroma, 308. 

Chorea, 234, 487. 

Chromatopsia, 478. 

Chronic diseases, distinctive character of, 
from acute, 382. 

Cicatrices, diagnostic importance of, 
412. 

Cirrhosis, 300, 320. 

Clapotage, 448. 

Claudication, 394. 

Clinics, application of scientific proce- 
dures to, 492-512. 

Coccidia, 115. 

Cold, 46; action of, upon the organism, 
49; therapeutic application of, 51; ac- 
tion of, upon bacteria, 125; role of, in 
infections, 142. 

Colitis, 103. 

Colles's law, 213. 



Commotion, effects of, upon the nervous 
system, 26. 

Consanguinity, 223 ; social, 223. 

Constipation, 130. 

Contagion, 134. 

Contracture, 463. 

Convalescence, 379. 

Copper, toxic role of, 66. 

Corset, deformities produced by, 447. 

Cough, 427. 

Crime and insanity, 236. 

Crisis, 376; definition of, 377; hematic, 
378. 

Cultivation of infectious agents, 87. 

Cuts, 18. 

Cysts, 303. 

• 

Death in general, 398; in infections, 
386; sudden, 182, 398. 

Decubitus, 404. 

Deformities, corporeal, 408. 

Degeneration, psychical stigmata of, 
238; cellular, various forms of, 317- 
327; causes of cellular, 319. 

Delirium, 487; of intelligence, 488. 

Dementia, 488. 

Diabetes, lean, 197; favorable to sup- 
puration, 261. 

Diaceturia, 202. 

Diagnosis, 1; serum, 510, 513-521. 

Diapedesis, 246. 

Diarrhoea, 130. 

Diathesis, definition of, 192. 

Dietetics, 2. 

Digestion, role of microbes in, 128. 

Digestive canal, bacteria in the, 128; 
poisons produced in the, under normal 
conditions, 129; under pathological 
conditions, 196; examination of the, 
438-453." 

Diphtheria, bacillus of, 107; toxines of, 
164; diagnosis of, 441. 

Disarthria, 489. 

Disease or diseases, 2; definition of, 4; 
distinction of, from affection, 6; 
causes of, 6; remote consequences of, 
4; infectious, definition of, 82; gen- 
eral pathogenesis of infectious, 158; 
none remains local, 329; evolution of, 
355-402; incubation of, 357; invasion 
of, 362; stationary period of, 365; 
clinical forms of, 371; crises in, 376; 



INDEX 



541 



convalescence from, 379, relapses and 
recurrences of, 381; passage of, to a 
chronic condition, 382; metastasis in, 
396; recovery from, 397; evolution of 
infectious, 357; evolution of noninfec- 
tious, 390; latent, 395; Addison's, 
412 ; Pott's, 408. 

Drugs, poisoning by, 79. 

Dyschromatopsia, 478. 

Dyslalia, 489. 

Dysphasia, 489. 

Dysphonia, 489. 

Dyspnoea, 427. 

Dystrophies, primitive autonomous ele- 
mentary, 8. 

Eclampsia, puerperal, 206. 

Electricity, 54; action of, upon the or- 
ganism, 56-58; upon bacteria, 126; 
therapeutic application of, 60; diag- 
nostic application of, 498; electrocu- 
tion, 59. 

Embolism, definition of, 339; classifica- 
tion of emboli, 340 ; effects of, 345, 349. 

Empiricism, 536. 

Endocarditis, vegetative or ulcerative, 
100, 102. 

Endothelioma, 308. 

Enteritis, 103. 

Environment, action of, upon the living 
organism, 3. 

Epilepsy, Jacksonian, 466. * 

Ergotism, 68. 

Erysipelas, 100; curative, 146, 315; ex- 
perimental, 247; period of incubation 
of, 359; relationship of, to puerperal 
fever, 290. 

Erythema, 410. 

Esophagus, examination of the, 442. 

Examination of the sick, 403-491. 

Exophthalmia, 473. 

Expectoration, 428. 

Explosions, effects of, upon the organ- 
ism, 24. 

Exudation, inflammatory and mechan- 
ical, 249. 

Eyes, effect of extirpation of the, upon 
the optic centres, 331. 

Facies, 405; dyspnoic types of, 406; 

grippe, 407 ; cholera, 407. 
Faecal matters, examination of, 444. 



Fever, 351; distinction of, from hyper- 
thermia, 351; of toxic origin, 353; con- 
tinued, 369; intermittent, 370; recur- 
rent, 112; yellow, 110; puerperal, 290; 
of overwork, 292; typhoid, 107. 

Fibroma, 308. 

Flint's murmur, 425. 

Foetus, pathology of the, 210-242. 

Frostbite, 48. 

Fungi, pathogenic, 87. 

Gait, disturbances of, 464. 

Gangrene, definition of, 266; dry and 

moist, 273; gaseous, 166. 
Gas, illuminating, as a volatile poison, 

69. 
Generation, spontaneous, 83. 
Genital apparatus, clinical examination 

of, 460. 
Germicidal action of the organism, 170. 
Glanders, bacillus of, 106; poison of, 167. 
Glands, lymphatic, protective role of, 

against pathogenic agents, 149; clin- 
ical exploration of, 413. 
Glioma, 308. 
Glycosuria, alimentary, 189; nervous, 

180. 
Gonococcus, micrococcus of gonorrhoea, 

105. 
Gonorrhoea, 105; lasting sequel of, 5. 
Gout, 188. 

Habit, 79. 

Hallucination, 488. 

Hearing, examination of, 478. 

Heart, puncture of the, 16; examination 
of the, 416. 

Heat, action of, upon the organism, 41 ; 
effects of, upon bacteria, 125; role of, 
in the development of infections, 142; 
heat stroke, 45. 

Helminthes, 94. 

Hemiopia, 477. 

Hemoptysis, 429. 

Heredity, 176, 220; distinction of, from 
innateness, 240; similar and homolo- 
gous, 225; of infectious diseases, 227; 
nervous, 231 ; progressive morbid, 232. 

Hippocratic fingers, 409 ; succussion, 437. 

Hutchinson's teeth, 228, 438. 

Hydrophobia, 149. 

Hygiene, 532. 



542 



INTRODUCTION TO THE STUDY OF MEDICINE 



Hypertrophy, ganglionic, 414; of the 

liver, 453. 
Hypnotism, 484. 
Hysteria, traumatic, 234. 

Icterus gravis, 103. 

Idiosyncrasies, 78. 

Illusion, 488. 

Immunity, 138; age and, 140; sex and, 
140; inherited, 229; active and pas- 
sive, 535. 

Inanition, 187. 

Incubation, 357 ; definition of, 357 ; vari- 
ation of period of, 359; period of, in 
various infectious diseases, 361. 

Infection, general etiology of, 133-157; 
abortive, 371; hetero-, 133-135; auto-, 
135-137; causes favourable to, 137; in- 
fluence of pregnancy upon the course 
of, 140; influence of fasting upon, 141 ; 
of overwork, 141; of cold and heat, 
142. 

Inflammation, 243-284; definition of, 
245; evolution of, 250; relationship 
between, and tumours, 313. 

Influenza, 109. 

Inoculation, 134; of microbes into ani- 
mals for diagnostic purposes, 511. 

Insanity, 235; genius, crime, and, 236. 

Insufficiency, cardiac, 334. 

Intellectual disturbances, 483. 

Intermittence in diseases, 393. 

Intestine, examination of the, 449. 

Intoxication, 62; evolution of diseases 
produced by, 390. See Auto-intoxica- 
tion, Toxines, and Poisons. 

Invasion, of, diseases, 362. 

Jacksonian epilepsy, 466. 
Jaundice, 411. 

Kidneys, examination of the, 459. 
Kussmaul's respiration, 430. 

Lalopathy, 489. 

Latency, period of, in slow poisoning, 
356; in visceral lesions, 3*93. 

Laveran's hematozoon, 370. 

Law of Brauell-Davaine, 212; of Colles, 
213; of Profeta, 214. 

Lead poisoning, 65. 

Lesion, local, 244, 367; mode of produc- 
tion of, 246; reparation of, 297. 



Letter blindness, 489. 

Leucocytes, phagocytic rCle of the, 170, 
246. 

Lientary, 446. 

Light, 52; pathogenic action of, 52-53; 
effects of, upon microbes, 125. 

Lipoma, 308. 

Liver, protective r6le of the, 152; indi- 
rect collaborator of the muscles, 332; 
hypertrophy of the, 453; examination 
of the, 453; palpation and percussion 
of the, 454. 

Lungs, absorption by the, 75; elimina- 
tion by the, 77; protective role of, 
against infections, 152; gangrene of 
the, 271; tuberculosis of the, 276; ex- 
amination of the, 427. 

Lymphadenitis, 414. 

Lymphatism, 193. 

Lymphoma, 308. 

Malaria, 370; intermittence in, 393. 

Malformations, congenital, 215. 

Measles, period of incubation of, 361. 

Melsena, 445. 

Meningitis, microbe of cerebro-spinal, 
102. 

Mensuration, 432 ; of cavities, 498. 

Mercury, poisonous effects of, 71. 

Metastasis, 396. 

Microbes, 88; distribution of, in water, 
119; in the soil, 120; in the air, 122; 
resistance of, 123; action of animate 
agents upon, 127; distribution of, in 
living organisms, 127; modes of en- 
trance of, into the organism, 147; 
protection of the organism against, 
149. See Bacteria and Agents, ani- 
mate. 

Micrococci, 88; specific, 105. 

Milk, influence of, upon fermentation, 
129; upon the number of bacteria in 
the digestive canal, 132. 

Monstrosity, 217. 

Motricity, disorders of, 462. 

Movements, influence of passive, upon 
the organism, 31. 

Murmurs, cardiac and extra-cardiac, 
423; pulmonary and pleural, 436; of 
recall, 420; galloping, 420; blowing, 
421, 436; varieties of, 422, 436. 

Myxoma, 308. 



INDEX 



543 



Naturism, 530. 

Nephritis, 300. 

Nervous system, heredity of the, 231- 
240; role of the, in cellular degenera- 
tions, 231; examination of the, 461- 
491. 

Neuroma, 308. 

Neurosis, barometric, 34. 

Nona, 484. 

Nosology, 1. 

Nutrition, principal characteristic of 
life, 184; the six acts of, 186; effects 
of starvation on, 187; disturbances of, 
188-209; disorders of, dependent upon 
disorders of digestion, 188; normal 
variations of, 189; influence of age 
upon, 190; variations of, under path- 
ological conditions, 191; diathesis a 
particular mode of, 193; auto-intoxi- 
cation under normal conditions of, 
196; auto-intoxication under patho- 
logical conditions of, 201; role of dis- 
orders of, in nervous and infectious 
diseases, 206; death due to arrest of, 
402. 

Nystagmus, 474. 

Occupation, poisonings due to, 70. 

Omentum, protective role of the, 150. 

Ophthalmoplegia, external, 474; inter- 
nal, 475. 

Opium, smoking of, 70. 

Opotherapy or organotherapy, 529. 

Osteoma, 308. 

Ovaries, role of the, in nutrition, 198; 
influence of extirpation of the, 331. 

Overwork, r6le of, in infection, 141; in- 
fluence of, upon urinary toxicity, 201 ; 
fever due to, 292. 

Oxide, carbonic, pathogenic action of, 
44, 71. 

Oxyures, 95. 

Pain, semeiological importance of, 470. 

Palpation of the skin, 412: of the pre- 
cordial region, 416; of the peripheral 
vessels, 425; of the chest, 433; of the 
stomach, 448; of the intestines, 449. 

Pancreas, effects of extirpation of the, 
197; examination of the, 455. 

Papilloma, 308. 

Paralysis, forms of, 462. 



Parasites, animal, 93 ; varieties of, 94 ; 
vegetable, 97. See also Microbes, Bac- 
teria, and Bacilli. 

Pathology, 1; comparative, 2; general, 
2, 536. 

Peptonuria, 188. 

Percussion of the heart, 417; of the 
lungs, 433 ; of the stomach, 449. 

Peritoneum, examination of the, 451. 

Peritonitis, 103. 

Phagedenism, 368. 

Phagocytosis, 170. 

Phobias, 487. 

Phosphorus, poisoning by, 71. 

Physiology, pathological, 1, 8. 

Pneumonia, 101; abortive, 371; clinical 
forms of, 374. 

Poisonings, treatment of, 527. 

Poisons, alimentary, 63; accidental ali- 
mentary, 65; volatile, 69; classifica- 
tion of, 63; modes of penetration of, 
74; transformation, elimination, and 
accumulation of, 76. See also Toxines. 

Pollakiuria, 456. 

Polyuria, 456. 

Pott's disease, 408. 

Pressure, atmospheric, 34; action of, 
upon bacteria, 124. 

Prof eta's law, 214. 

Prognosis, 1, 513-521; serum, 521. 

Prophylaxis, 2, 532. 

Pseudo-membranes, 251. 

Ptomaine, 159. 

Pulse, venous, 425; hepatic, 454; Corri- 
gan's, 415; Traube's, 419; examina- 
tion of the, 415. 

Punctures, 14; exploratory, 512. 

Pus, varieties of, 255 ; histology of, 256. 

Pyaemia, 285-294; classification of, 287; 
pathogenic agents of, 289 ; general eti- 
ology of, 289; evolution of, 292; at- 
tenuated forms of, 293; distinction of, 
from septicaemia, 293. See also Septi- 
caemia. 

Race, importance of, in resistance to in- 
toxications, 78; to infections, 138. 

Bales, distinction of, from frictions, 435 ; 
varieties of, 435-436. 

Reactions, nervous, 173-183; general, 30, 
169, 173; psychical, 177; nutritive, 
180; local and general, 249; general 



544 



INTRODUCTION TO THE STUDY OF MEDICINE 



inflammatory, 251; fever dependent 
upon, 352. 

Recovery, 397. 

Recurrence, 381; diseases liable to fre- 
quent, 381. 

Reflexes, tendon, clinical investigation 
of, 468, 469. 

Relapse, 381. See also Recurrence. 

Respiration, examination of, 430 ; Cheyne- 
Stokes, 430; Kussmaul's, 430; expira- 
tory, of Bouchut, 431. 

Revulsion, 396, 531. 

Rheumatism, acute articular, 112. 

Rifles, models of, 22. 

Sarcoma, 308. 

Sclerosis, 298; role of, 299, 385. 

Scrofulosis, 193. 

Seasons, influence of, upon the develop- 
ment of infections, 137. 

Selection, natural and social, 241. 

Sense, muscular, 472. 

Sensibility, examination of, 470. 

Septicaemia, agents of, 104; poisons of, 
166; definition of, 285. See also 
Pyaemia. 

Serum, germicidal, 526; injection of arti- 
ficial, 527, 535. 

Sex, importance of, in resistance to poi- 
sons, 78 ; to infections, 140. 

Shock, nervous, 30, 181. 

Sickness, mountain, 37; seasickness, 32; 
sleeping, 484. 

Sight, examination of, 473. 

Sign, Argyll-Robertson, 475; Kernig's, 
463; Lichtheim's, 490; Westphal's, 
469. 

Skin, microbes of the, 127; infections of 
the, 147; elimination of toxic sub- 
stances by the, 196; clinical examina- 
tion of the, 410-413. 

Skodism, 433. 

Sleep, modifications of, 483. 

Sleeping sickness, 484. 

Small-pox, incubation period of, 361. 

Smell, examination of, 479. 

Soil, microbes of the, 120. 

Somnambulism, 485. 

Sound, action of, upon the organism, 53. 

Speech, troubles of, 488. 

Spermatorrhoea, 460. 

Spirilla, 89. 



Spleen, examination of the, 455. 

Spores of microbes, 88-90. 

Sputa, varieties of, 428; microscopic ex- 
amination of, 506. 

Staphylococcus, 88, 98. 

Starvation, 187. 

Steppage, 464. 

Stomach, deformities of the, 447; exam- 
ination of the, 442. 

Streptococcus, 88; pathogenic species of, 
99-101. 

Suicide, 72. 

Sunstroke, 45. 

Suppuration, 255-266; mechanism of, 
257; pyogenic agents of, 258. 

Surgery, 2. 

Sympathies, morbid, 328-354; between 
the heart and the lungs, 403. 

Symptoms, 9. 

Syncope, 407. 

Synergy, 328. 

Syphilis, conceptional, 214; hereditary, 
213. 

Taenia, varieties of, 95. 

Taste, examination of, 479. 

Teeth, examination of the, 438. 

Temperament, epidemic, 34. 

Testicles, role of the, in nutrition, 198. 

Tetanus, 165. 

Therapeutics, 2, 11, 522-536; symptom- 
atic, 522; etiological, 523; psychical, 
531; perturbating, 532. 

Thermometry, 496. 

Throat, examination of the, 441. 

Thyroid gland, role of, in nutrition, 197. 

Tongue, examination of the, 440. 

Toxic equivalents, 78. 

Toxines, definition of, 62 ; exogenous and 
endogenous, 63; cause of infectious 
manifestations, 82; bacterial, 164; ac- 
tion of, upon the organism, 169; most 
important chemical agents, 527. 

Traumatism, role of, in microbic local- 
izations, 155; in the development of 
tumours, 312; internal, 182. 

Tubercles, 274; localization and evolu- 
tion of, 276. 

Tuberculosis, 109; inoculability of, 85; 
toxines of, 168; congenital and hered- 
itary, 214; acute miliary, 280; of 
animals, 281; of inoculation, 276. 



INDEX 



545 



Tumours, 305-316; benign and malig- 
nant, 305; classification of, 309; em- 
bryological, 306; histogenetic, 307; 
typical and atypical, 310; etiology of, 
311; role of traumatism in the produc- 
tion of, 312; pathogenesis of, 313. 

Typhoid fever, 107; aqueous origin of, 
108; poison of, 167; clinical forms of, 
375; walking, 395. 

Ulcer, 384. 

Uraemia, 205. 

Urine, toxicity of the, 200 ; variations of, 
in infections, 378; incontinence and 
retention of, 456; clinical examina- 
tion of, 457-459; chemical analysis 
of, 502. 

Vaccination, 532; Jennerian, 533; Pas- 
teurian, 534; insensible, 139. 



Vasomotor, phenomena in nervous re- 
actions, 51, 178. 

Venomous animals, 67; insects, 74. 

Venoms, 73. 

Vertigo, 485. 

Virulence, gravity of infection depend- 
ent upon the degree of, 156. 

Vision. See Sight. 

Vomiting, 443. 

Water, poisons contained in, 65; mi- 
crobes of, 119; typhoid bacillus in, 
108. 

Weighing of patients, 496. 

Word blindness, 490. 

Word deafness, 489. 

Wounds, simple and complicated, 17; 
caused by firearms, 20; contused, 25. 

Yellow fever, 110. 



THE END 



THE PRINCIPLES AND PRACTICE 
OF MEDICINE. 

By WILLIAM OSLER, M. D., 

Fellow of the Royal College of Physicians, London; Professor of Medicine in the Johns Hopkins Univer- 
sity, and Physician in Chief of the Johns Hopkins Hospital, Baltimore; formerly Professor of 
the Institutes of Medicine, McGill University, Montreal; and Pi ofessor of Clinical 
Medicine in the University of Pennsylvania, Philadelphia. 



THE WORK HAS BEEN REWRITTEN, ENLARGED, ENTIRELY RESET, 
AND BROUGHT UP TO DATE IN ALL DEPARTMENTS. 



THIRD EDITION. 
SOLD ONLY BY SUBSCRIPTION. 



8vo, 1181 pages. Cloth, $5.50; sheep, $6.50; half morocco, $7.00. 



" With new type, clear paper of the best quality, and a somewhat enlarged page, necessi- 
tated by the amount of matter in the very thorough revision of a book whose first edition 
appeared six years ago, Osier's Practice comes to us with that handsome entourage its prime 
excellence, merit, and true value demand. . . . From first to last, title-page to index, the 
work is thoroughly practical, and as a guide in diagnosis, symptomatology, and treatment, 
will be found well-nigh incomparable, and can not but be the more appreciated the more its 
sound advice and wise counsel are sought, whether by the neophyte in medicine or the most 
experienced clinician." — Southern Practitioner. 

" We have little to add to 6ur notice of the second edition {vide Journal, November 30, 
1895, page 966). The criticisms then made hold good now, but we regarded the work as ore 
of the ablest contributions to the literature of the subject in this country, an opinion which 
we still hold." — Journal of the American Medical Association. 

" The first edition was great, the second greater, and this last greatest of all." — Cincin- 
nati Lancet-Clinic. 

" There are few books which receive professional confidence and esteem to the extent of 
that received by Dr. Osier's well-known work, for three large editions have been presented to 
us in a period of about six years." — Therapeutic Gazette. 

" The work, like former editions, is thoroughly practical in its character, fully up with the 
times and down to date, and is a safe guide to all practitioners who may consult its pages. 
The student of medicine, whose time is so much occupied by the tremendous amount of 
knowledge he is expected to master before graduation, will find here exhaustiveness without 
verbosity and a plain matter-of-fact method of discussing the characters of different diseases, 
that can not fail to instruct without wearying." — Journal of Medicine and Science. 



D. APPLETON AND COMPANY, NEW YORK. 



A New, Thoroughly Revised, and Enlarged Edition of 

QUAIN'S 
DICTIONARY OF MEDICINE. 

BY VARIOUS WRITERS. 

Edited by Sir RICHARD QUAIN, Bart., M. D., LL. D., etc., 

Physician Extraordinary to Her Majesty the Queen ; Consulting Physician to the Hospital for Diseases 

of the Chest, Brompton, etc. 

Assisted by FREDERICK THOMAS ROBERTS, M. D., B. Sc, 

Fellow of the Royal College of Physicians, etc. ; 

And J. MITCHELL BRUCE, M.A., M. D., 

Fellow of the Royal College of Physicians, etc. 

With an American Appendix by SAMUEL TREAT ARMSTRONG, Ph. D., M.D., 

Visiting Physician to the Harlem, Willard Parker, and Riverside Hospitals, New York. 



IN TWO VOLUMES. Sold only by subscription. 

This work is primarily a Dictionary of Medicine, in which the several diseases are fully 
discussed in alphabetical order. The description of each includes an account of its etiology 
and anatomical characters ; its symptoms, course, duration, and termination ; its diagnosis, 
prognosis, and, lastly, its treatment. General Pathology comprehends articles on the origin, 
characters, and nature of disease. 

General Therapeutics includes articles on the several classes of remedies, their modes of 
action, and on the methods of their use. The articles devoted to the subject of Hygiene treat 
of the causes and prevention of disease, of the agencies and laws affecting public health, of 
the means of preserving the health of the individual, of the construction and management of 
hospitals, and of the nursing of the sick. 

Lastly, the diseases peculiar to women and children are discussed under their respective 
headings, both in aggregate and in detail. 

The American Appendix gives more definite information regarding American Mineral 
Springs, and adds one or two articles on particularly American topics, besides introducing 
some recent medical terms and a few cross-references. 

The British Medical yournal says of the new edition : 

4 ' The original purpose which actuated the preparation of the original edition was, to 
quote the words of the preface which the editor has written for the new edition, ' a desire to 
place in the hands of the practitioner, the teacher, and the student a means of ready reference 
to the accumulated knowledge which we possessed of scientific and practical medicine, rapid 
as was its progress, and difficult of access as were its scattered records.' The scheme of the 
work was so comprehensive, the selection of writers so judicious, that this end was attained 
more completely than the most sanguine expectations of the able editor and his assistants 
could have anticipated. ... In preparing a new edition the fact had to be faced that never 
in the history of medicine had progress been so rapid as in the last twelve years. New facts 
have been ascertained, and new ways of looking at old facts have come to be recognized as 
true. . . . The revision which the work has undergone has been of the most thorough and 
judicious character. . . . The list of new writers numbers fifty, and among them are to be 
found the names of those who are leading authorities upon the subjects which have been 
committed to their care." 



D. APPLETON AND COMPANY, NEW YORK. 



THE DISEASES OF 

THE NEKVOUS SYSTEM. 

A TEXT-BOOK FOR PHYSICIANS AND STUDENTS. 

By Dr. LUDWIG HIKT, 

PROFESSOR AT THE UNIVERSITY OF BRESLATT. 

SECOND AMERICAN EDITION, REVISED FROM THE SECOND GERMAN EDITION 

By AUGUST HOCH, M. D., 

ASSISTED BT 

FRANK R. SMITH, A. M. (Cantab.), M. D., 

ASSISTANT PHYSICIANS TO THE JOHNS HOPKINS HOSPITAL. 

WITH AN INTRODUCTION 
By WILLIAM OSLER, M. D., F. R. C. P., 

PROFESSOR OF MEDICINE IN THE JOHNS HOPKINS UNIVERSITY, AND PHYSICIAN IN CHIEF TO THE 

JOHNS HOPKINS HOSPITAL, BALTIMORE. 

8vo, 715 pages. With 181 Illustrations. 
Cloth, $5.00; sheep, $6.00. 



" This work possesses many points which are sufficiently novel to justify its transla- 
tion and publication in this country. The general practitioner is perhaps more in need 
of reliable text-books on diseases of the nervous system than is the specialist. . . . The 
volume before us admirably meets his requirements, and to a very great extent covers 
those parts of the study which have not been fully presented by former writers. . . . 
The work of the translators is perfect, leaving no trace of the German idioms." — Ohio 
Medical Journal. 

" The profession of this country stands under the greatest obligation to the trans- 
lators of this standard work for having thus furnished the opportunity of making use of 
one of the best works ever published upon the subject. As a work of reference to the 
physician it has no equal. To specialists in this branch of diseases it is invaluable. As 
features of especial commendation may be mentioned the author's clearness in the ana- 
tomical and symptomatological arrangement of diseases." — Nashville Journal of Medicine 
and Surgery. 

" The translators of this volume have conferred a favor upon English-reading mem- 
bers of the profession bv their excellent rendering of the work of Professor Hirt. The 
text is especially valuable for the clear, accurate, and well-ordered description of 
pathological anatomy and symptomatology. As regards treatment, the author may be 
accepted as a safe guide. . . . The typography and plates of this work are all that can 
be desired." — Medical Bulletin. 



D. APPLETON AND COMPANY, NEW YORK. 



A TREATISE ON THE 

PRACTICE OF MEDICINE, 

FOR THE USE OF STUDENTS AND PRACTITIONERS. 
By ROBERTS BARTHOLOW, M. A., M. D., LL. D., 

Late Professor of Materia Medica and General Therapeutics in the Jefferson Medical Col- 
lege of Philadelphia ; formerly Professor of the Practice of Medicine and of 
Clinical Medicine in the Medical College of Ohio at Cincinnati, etc. 



Seventh Edition^ revised and enlarged. 8vo. 1003 pages. 
Cloth, $5.00; sheep, $6.00. 



" The. large number of readers who are already familiar with this work will be glad 
to learn that the present edition has been carefully revised by the author, considerably 
enlarged, and is intended to include all that has in the most recent period been added to 
practical medicine, especially in its clinical horizon. The author felicitates himself on 
the large sales obtained for the previous editions, and there is no reason why the present 
one should not continue to gain in the opinion of many. What doubtless lends the vol- 
ume one of its special attractions to these is the authoritative expressions which are fre- 
quent in its pages on subjects where the reader might be left in uncertainty elsewhere. 
This remark applies both to pathology and treatment. The fullness with which thera- 
peutics are taught stands in noteworthy contrast to the majority of treatises on practice. 
This, too, is undoubtedly a feature which will be agreeable to numerous purchasers. 
Some seeming excess of conciseness in certain portions is explained by the fact that this 
is but one volume of a scries proposed by the author, which will cover the whole domain 
of special pathology and therapeutics." — Medical and Surgical Reporter. 

" This valuable work appears in its sixth edition considerably enlarged, and improved 
materially in many respects. The arrangement of the subjects appears to be pretty much 
the same as in former editions, and the description of diseases is also little modified. 
Some new chapters have been added, however, and new subjects introduced, making the 
volume completely cover the entire domain of practice, without anything superfluous. 
Considering the immense scope of subjects, the directness of statement, and the plain, 
terse manner of dealing with the phenomena of disease, this practical work has no counter- 
part." — Kansas City Medical Record. 

" That six editions of such a work should be called for in six years is perhaps the 
most flattering testimonial that a book can receive, and must outweigh every other com- 
ment, favorable or unfavorable. In the preface to this edition is an announcement which 
will be welcomed by all of Dr. Bartholow's numerous admirers, namely, that he has now 
in preparation another work on the ' Principles of Medicine,' which, together with the 
one under review, and his c Materia Medica and Therapeutics,' shall constitute a trio of vol- 
umes each containing matter complementary to the others. Certainly three such volumes 
must constitute a monument which will render the writer's fame almost undying." — 
Medical Press of Western New York. 



D. APPLETON AND COMPANY, NEW YORK. 



JAN 19 1901 



